Computer Networks As Social Networks Barry Wellman

C OMPUTERS AND S CIENCE

ing of ESTs that substantially alleviated, even if they and kindred U.S. legislation, see, e.g., J. H. Reichman, P. 37. The role of scientiﬁc organizations in facilitating did not totally resolve, this threat to science from Samuelson, Vanderbilt Law Rev. 50, 51 (1997). changes in U.S. policy is recounted in (38). overbroad patent rights. 36. See, e.g., National Research Council, Bits of Power: 38. P. Samuelson, Va. J. Intl. Law 37, 369 (1997). 34. Directive 96/9/EC of the European Parliament and of Issues in Global Access to Scientiﬁc Data (National 39. These efforts are recounted by J. H. Reichman and the Council of 11 March 1996 on the Legal Protection Academy of Sciences Press, Washington, DC, 1997) P. F. Uhlir [Berkeley Technol. Law J. 14, 793 (1999)]. of Databases, 1996 O.J (L 77) 20. (expressingconcernaboutEuropeanUnion–styledata- 40. I gratefully acknowledge research support from NSF 35. For a critical commentary on the EU database directive base protection). grant SEC-9979852.

VIEWPOINT Computer Networks As Social Networks Barry Wellman

Computer networks are inherently social networks, linking people, orga- first, computer scientists would be saying nizations, and knowledge. They are social institutions that should not be “netware” instead of “groupware” for sys- studied in isolation but as integrated into everyday lives. The proliferation tems that enable people to interact with each of computer networks has facilitated a deemphasis on group solidarities at other online. Often computer networks and work and in the community and afforded a turn to networked societies social networks work conjointly, with com- that are loosely bounded and sparsely knit. The Internet increases people’s puter networks linking people in social net- social capital, increasing contact with friends and relatives who live nearby works and with people bringing their offline and far away. New tools must be developed to help people navigate and situations to bear when they use computer ﬁnd knowledge in complex, fragmented, networked societies. networks to interact. The intersection of computer networks Once upon a time, computers were not cial network of them all. Just one small por- with the emerging networked society has fos- social beings. Most stood alone, be they tion of the Internet—Usenet members—par- tered several exciting developments. I report mainframe, mini, or personal computer. ticipated in more than 80,000 topic-oriented here on two developing areas: (i) community Each person who used a computer sat alone collective discussion groups in 2000. 8.1 mil- networks on- and offline and (ii) knowledge in front of a keyboard and screen. To help lion unique participants posted 151 million access. people deal with their computers, the field messages (2–4). This is more than three times of human-computer interaction (HCI) de- the number identified on 27 January 1996 (5) Community Networks On- and Ofﬂine veloped, providing such things as more Computer scientists and developers have Community, like computers, has become net- accessible interfaces and user-friendly soft- come to realize that when computer systems worked. Although community was once syn- ware. But as the HCI name says, the model connect people and organizations, they are onymous with densely knit, bounded neigh- was person-computer. inherently social. They are also coming to borhood groups, it is now seen as a less Computers have increasingly reached out realize that the popular term “groupware” is bounded social network of relationships that to each other. Starting in the 1960s, people misleading, because computer networks prin- provide sociability support, information, and began piggybacking on machine-machine cipally support social networks, not groups. a sense of belonging. These communities are data transfers to send each other messages. A group is only one special type of a social partial (people cycle through interactions Communication soon spilled over organiza- network; one that is heavily interconnected with multiple sets of others) and ramify tional boundaries. The proliferation of elec- and clearly bounded. Much social organiza- through space [a low proportion of commu- tronic mail (e-mail) in the 1980s and its tion no longer fits the group model. Work, nity members in the developed world are expansion into the Internet in the 1990s community, and domestic life have largely neighbors (7)]. Where once people interacted (based on e-mail and the Web) have so tied moved from hierarchically arranged, densely door-to-door in villages (subject to public things together that to many, being at a com- knit, bounded groups to social networks. support and social control), they now interact puter is synonymous with being connected to In networked societies, boundaries are household-to-household and person-to-per- the Internet. more permeable, interactions are with diverse son (9). As a result, HCI has become socialized. others, linkages switch between multiple net- Although the support of collaborative Much of the discussion at current HCI con- works, and hierarchies are flatter and more work was the initial purpose of the Internet ferences is about how people use computers recursive (6–8). Hence, many people and or- (both e-mail and the Web), it is an excellent to relate to each other (1). Some participants ganizations communicate with others in ways medium for supporting far-flung, intermit- build “groupware” to support such interac- that ramify across group boundaries. Rather tent, networked communities. E-mail tran- tions; others do ethnographic, laboratory, and than relating to one group, they cycle through scends physical propinquity and mutual survey studies to ascertain how people actu- interactions with a variety of others, at work availability; e-mail lists enable broadcasts to ally relate to each other. This work has slowly or in the community. Their work and com- multiple community members; attachments moved from the lone computer user to deal- munity networks are diffuse and sparsely and Web sites allow documents, pictures, and ing with (i) how two people relate to each knit, with vague overlapping social and spa- videos to be passed along; buddy lists and other online, (ii) how small groups interact, tial boundaries. Their computer-mediated other awareness tools show who might be and (iii) how large unbounded systems oper- communication has become part of their ev- available for communication at any one time; ate—the ultimate being the worldwide Inter- eryday lives, rather than being a separate set and instant messaging means that simulta- net, the largest and most fully connected so- of relationships. neous communication can happen online as When computer-mediated communication well as face-to-face and by telephone. networks link people, institutions, and knowl- Systematic research on what people ac- Centre for Urban and Community Studies, University of Toronto, 455 Spadina Avenue, Toronto, Canada edge, they are computer-supported social net- tually do on the Internet has lagged behind M5S 2G8. E-mail: [email protected] works. Indeed, if Novell had not gotten there the Internet’s development. After a long

www.sciencemag.org SCIENCE VOL 293 14 SEPTEMBER 2001 2031 C OMPUTERS AND S CIENCE period of pundit supposition, travelers’ tales, now used by a majority of North Ameri- tained; new ties are developed among people and laboratory studies of computer-mediated cans, although its growth rate is slowing sharing interests. It is not only that time and communication, survey-based and ethnograph- and may stabilize at about 60% of adults. space become less important in computer- ic research is now appearing. The digital divide is decreasing rapidly in mediated communication, but that it is easy These studies address a vigorous public North America, although socioeconomic to communicate with large groups of commu- debate about whether people can find com- status (education, occupation, and income) nity members (using lists) and to bring un- munity online. Critics wonder whether rela- remains an important differentiator (17– connected community members into direct tionships between people who never see, 20). The digital divide is much more sig- contact. The ease with which computer-me- smell, or hear each other can be the basis for nificant in two ways in less developed diated communication connects friends of true community [reviewed in (10); examples countries: (i) A much lower percentage of friends can also increase the density of inter- include (11–13)]. Other detractors make an the population use the Internet and (ii) the connections among clusters of network mem- opposite argument: The Internet may be so users are predominantly well-connected bers within communities. immersive that it lures people away from elites (21). In the developed world, the For one thing, as the newbies studied by other pursuits (14) and involves them in on- amount of time spent online is increasing, Kraut et al. (33) gained more experience with line interactions that only reinforce their ex- per capita as well as overall. For example, the Internet, their depression and alienation isting opinions. the average AOL user spent 31 min per day disappeared, and their social contact in- By contrast, enthusiasts see the Internet online in the first quarter of 1997; in 4 creased enough to have a positive impact on as extending and transforming community. years, this had more than doubled to 64 min their overall interactions with community John Perry Barlow asserts that “with the online in the first quarter of 2001 (22). Nor members. A comparative analysis found that development of the Internet...wearein does familiarity breed interpersonal con- social support obtained online helped people the middle of the most transforming tech- tempt: The more contact people have on- to deal with depression (34). nological event since the capture of fire” line, the greater the impression they make Other studies have found that the Internet (15). They point to the ability of the Inter- on each other (23). increased community interaction (35, 36). net to span distances and time zones at low Survey-based evidence about the Inter- For example, a large National Geographic cost, to sustain relationships based on net’s effect on community has been mixed. Web survey found that face-to-face visits and shared interests (even when the participants Most cross-sectional studies show that those phone calls were neither more numerous nor are residentially dispersed), and to provide frequently online are more involved in com- fewer for people who use e-mail a great deal. powerful links between people and dis- munity (24–27). By contrast, one study (28) E-mail just added to the fund of contact, so persed knowledge (16). suggests that extensive online involvement that the overall volume of contacts with Too often the debate has been (i) took people away from interaction with friends and relatives through all media was Manichean: The Internet is bringing heaven household and community members. More- higher for people who use e-mail a lot (27) or hell, but nothing in between. (ii) Unidi- over, the only true longitudinal study found (Table 1). mensional: The Internet is such a powerful that some “newbies” became more depressed, However, another study found that e-mail force that other considerations, such as gen- alienated, and isolated during the first 6 use is displacing telephone use to some extent der and status in an organization, are ignored. months of computer use (29). (37). Perhaps there are differences in the (iii) Parochial: The Internet should be consid- Robust results indicating how the Internet kinds of communication that take place on ered as an entity in itself, rather than as fitting fits into community life are now available the Internet or by telephone or face-to-face. into the full range of work, community, and (30–32). It is becoming clear that the Internet Although one study of a dispersed work daily life. (iv) Presentist: The Internet is such is not destroying community but is resonating group found much similarity in what was said a transforming force that long-term social with and extending the types of networked by means of each of these media (26), anoth- trends, such as the pre-Internet move to net- community that have already become preva- er found that among community members, worked communities, are irrelevant. lent in the developed Western world. Old ties e-mail is preferred more when people want to As the debate continues, the Internet is with relatives and former neighbors are main- garner information efficiently.

Table 1. E-mail use by total annual communication. [Source: Survey2000; see (27) for details]

Kin Friends E-mail use F2F* Phone Letters E-mail Total F2F Phone Letters E-mail Total

Within 50 km Never 77 117 6 1 201 104 136 6 1 247 Rarely 65 116 6 5 192 84 112 8 5 209 Monthly 61 113 6 7 187 74 98 5 9 186 Weekly 62 120 6 13 201 76 99 7 20 202 Few times/week 63 115 7 24 209 83 113 7 37 240 Daily 60 118 8 52 178 92 126 9 118 345 Total 61 117 7 39 224 88 120 9 86 303 Beyond 50 km Never 12 37 8 1 58 13 25 7 1 46 Rarely 10 36 8 5 59 11 19 7 4 41 Monthly 9 35 7 10 61 8 16 6 8 38 Weekly 9 36 9 19 73 8 17 6 16 47 Few times/week 10 39 9 35 93 9 19 7 30 65 Daily 10 43 10 72 135 10 25 8 85 128 Total 10 41 10 55 116 10 23 8 62 103 *F2F, face to face.

2032 14 SEPTEMBER 2001 VOL 293 SCIENCE www.sciencemag.org C OMPUTERS AND S CIENCE The positive impact of the Internet on al Geographic Survey2000 data are available Another approach, Babble, builds on the community ties is true for those living both for use [(27, 46); see http://survey2000. traditional groupware approach, which facil- nearby and far away. The proportionate gain nationalgeographic.com]. The National Geo- itates a small defined group working together in contact is greatest for contact with friends graphic Society (in conjunction with Clem- (59). Babble shows each person as an animat- and relatives living at a distance (9, 38), as son University and the University of Toronto) ed and colored circle that moves closer to the one might expect from a system able to cross is doing an even larger and more comprehen- center as the person gets more involved in time zones at a single bound and in which sive Web survey in fall 2001. A University of team activities. there is no differentiation between short-dis- Maryland “Web institute” is archiving many When people are asked about the size of tance and long-distance messages. Yet online surveys online with statistical software avail- their networks, they consistently report them as well as offline contact is highest with those able for reanalysis (47). Along with such as smaller than the 1000 or more others that living nearby (9, 38). Cyberspace does not survey efforts, there is scope for ethnographic they probably know well enough to converse vanquish the importance of physical space. community studies [such as what Hampton with (60–62). Rolodexes and their database For example, many e-mail and chat messages and Wellman have done in Netville (38, 40, equivalents are some help, but the listing can arrange face-to-face meetings (26, 39). 47–49)]. be computer-supported. ContactMap (52) The recent case of “Netville” (a suburb of looks at ongoing Internet exchanges to record Toronto) is especially interesting, because Finding Knowledge in a Networked a person’s contacts. here neighborhood access to a high-speed Society Such memory aids typically record each Internet service helped bring neighborhood Many organizations are similar to networked person as a discrete entity. New develop- members together for face-to-face get-togeth- communities in having multiple sets of work ments record the connections of network ers, from visits in private homes to semi- team members (including multiple superiors), members (63, 64). As such approaches de- public barbeques (40, 41). Those who were physically dispersed relationships, and teams velop, they have the potential to do primitive part of the high-speed service knew three of co-workers shifting by the day and week as automated social network analysis—identify- times as many neighbors as the unwired and employees get involved in multiple projects. ing clusters, boundaries, centrality, bridges, visited with 1.6 times as many. Nor was the The situation is different from that dealt with and blocks—by analyzing who jointly re- Internet only used socially: Netville residents by traditional organizational theory, which ceives an e-mail and who forwards e-mails to used their local discussion list to mobilize comprehends densely knit workgroups neatly whom. against the real estate developer and the local structured in bureaucratic, hierarchical orga- Who holds the organizational or commu- Internet service provider (40). To be sure, nizational trees (6, 50–52). nity memory, now that the veteran employ- Netville may be a special case because the How do people work together in large, ee—the fount of work lore—is neither known residents were newly arrived and excited to sprawling, networked organizations where nor accessible? Often people ask their work- be part of an Internet experiment. Yet recent they are simultaneously members of multiple, mates. But what if they do not know? People work in Michigan (42) and Los Angeles (43) transitory, physically dispersed teams? In then wonder whether friends of friends know, shows how the Internet can reinforce tradi- particular, how do people in such organiza- yet most people do not possess a list of all of tional community development approaches. tions obtain knowledge from others when their friends’ friends, much less are aware of Despite the past decade’s excitement they do not know whom to ask? what their friends’ friends know. Yet it is about the Internet, as it pervades life it may These questions are of immediate practi- reasonable to assume that the number of become as taken for granted as that once- cal importance for complex organizations. friends of friends is 100,000, assuming that transforming technology, the telephone (44). Hence, computer-supported solutions are de- each person knows approximately 1000 oth- One indication is that those who have been on veloping for working through trusted inter- ers and that 10 percent of each person’s ties the Internet the longest and the most fre- personal relationships to identify, locate, and are unique. These are too many names to quently are least apt to feel that they are a part receive information within and between com- keep track of, yet people often want a per- of an online community, although their over- munities and organizations. It is not surpris- sonal touch when giving and getting informa- all sense of community remains (27). This ing that work in this area has been driven by tion. They may want to talk to the informa- may reflect their greater likelihood of en- computer scientists and communication sci- tion holder to supply a nuanced or confiden- countering distasteful situations, such as entists interested in building tools for knowl- tial request; the information holder may only flaming, hacking into accounts, virus trans- edge access and management. be willing to release such information to a mission, or unwanted junk mail “spam.” Or it One issue is finding out who knows what; friend or a friend of a friend. may mean that those with much Internet ex- a more complex task in networked organiza- IKNOW is software that stores informa- perience do not privilege it as a special form tions (53). Normally, one attempts to exam- tion about friends of friends; not only who of community. Or it may support the fears of ine the documentation or other help sources they are but what information they know those who believe that computer-mediated and then wanders out into a hallway in search (65). It seeks to answer the question: “Who communication is not a satisfactory surrogate of friendly colleagues. The problem becomes knows who knows what?” The hope is that for face-to-face contact. acute, however, in distributed communities through the use of such indirect but personal Thus, preliminary findings create new [(54), p. 97]. ties, people will supply reliable and appropri- questions. At present, Internet studies of How do people wander the hallway when ate information. Issues remain. The first is community are in full swing: The Pew Inter- their team or other supports are physically about software that is scalable to map and net and American Life project does a monthly distributed? One approach is to build aware- supply such contact information for a large tracking study (35). The Stanford Institute for ness tools (55). Two of these, Cruiser (56) amorphous organization. The second is about the Quantitative Study of Society is doing and Postcards/Telepresence (57, 58), provid- data collection: How do systems compile in- frequent surveys (14, 45). The U.S. General ed low-resolution video pictures of offices or formation about who knows what? The third Social Survey, which is central to social sci- cubicles. The picture told others whether peo- is about privacy: Do people want to reveal ence research, included an Internet module in ple were in their offices and perhaps avail- their friends and their skill sets to strangers? 2000 and may do so again. The 2001 Cana- able. The low resolution of the picture was The Answer Garden (54) addresses such dian General Social Survey has an Internet not able to show what people were doing and issues of data collection and privacy, al- module. The large-scale international Nation- afforded some privacy. though it does not deal with interpersonal

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connections. It provides tools for people to 12. M. Slouka, War of the Worlds: Cyberspace and the 46. J. C. Witte, L. M. Amoroso, P. E. N. Howard, Social Sci. build repositories of commonly requested High-Tech Assault on Reality (Basic Books, New York, Comput. Rev. 18, 179 (2000). 1995). 47. The archive at www.webuse.umd.edu contains origi- questions and answers, in part by building up 13. V. Jergens, “Does the Internet Bring Us Down,” New nal data from more than 20 surveys in which behav- these repositories from ongoing question- York Times, 3 September 1998 (online at www. ioral questions about Internet usage were asked of and-answer sessions. Thus, only the informa- nytimes.com). nationally representative samples, including the Dig- 14. N. Nie, Am. Behav. Sci., in press. ital Divide surveys done by the U.S. Census Bureau tion that has been publicly provided is avail- 15. J. P. Barlow, S. Birkets, K. Kelly, M. Slouka, Harper’s for the NTIA, the 2000 U.S. General Social Survey, able. However, this provides only limited 1995, 40 (August 1995). and national time use surveys. Users can directly access to the files of each work team member. 16. H. Rheingold, The Virtual Community (MIT Press, analyze the data interactively using statistical soft- Good solutions are not yet available that bal- Cambridge, MA, ed. 2, 2000). ware. In addition to the data archive, the Web site 17. M. Kew, B. Wellman, Curr. Sociol., in press. contains an annotated bibliography of behavioral re- ance team needs to have access to personal 18. A. Reddick, C. Boucher, M. Groseillers, The Dual Dig- search into more than 15 areas of Internet use (such files with the needs of each person to limit a ital Divide: The Information Highway in Canada (Pub- as the digital divide, time displacement, and social team’s access to only the germane portions of lic Interest Advocacy Centre, Ottawa, Canada, 2000). networks), articles on Internet behavior, and links to 19. National Telecommunications and Information Ad- other resources. his or her entire files. ministration (NTIA), Falling Through the Net (NTIA, 48. B. Hampton, B. Wellman, Am. Behav. Sci. 43, 475 With so much potential and need to con- Washington, DC, 2000). (1999). nect, there is the need to prioritize communi- 20. E. Fong, B. Wellman, R. Wilkes, M. Kew, Correlates of 49. N. K. Baym, in Culture of the Internet, S. Kiesler, Ed. the Digital Divide: Individual, Household and Spatial cation. Does my boss supersede my peers? (Lawrence Erlbaum, Mahwah, NJ, 1997), pp. 103–120. Variation (report to Ofﬁce of Learning Technologies, 50. N. S. Contractor, Manage. Commun. Q. 13, 154 Does my wife or husband have higher prior- Human Resources Development Canada, Ottawa, (1999). ity than my sister or brother? Dealing with Ontario, June 2001). 51. N. Nazer, thesis, University of Toronto (2000). 21. W. Chen, J. Boase, B. Wellman, in The Internet in such matters would be an advanced imple- 52. B. A. Nardi, S. Whittaker, H. Schwartz, First Monday 5, Everyday Life, B. Wellman, C. Haythornthwaite, Eds. 30 (2000). mentation for the simple filter rules now (Blackwell, Oxford, in press). 53. R. Cross, S. Borgatti, The Ties that Share: Relational commonly available for e-mail. Important, as 22. A. Odlyzko, The History of Communications and its Characteristics that Facilitate Knowledge Transfer and yet unpublished, work is being done to estab- Implications for the Internet (AT&T Labs-Research, Organizational Learning (working paper of the Carroll Florham Park, NJ, 2000). School of Management, Boston College, Boston, MA, lish rules for prioritizing computer-mediated 23. Y. Liu, The Effects of Frequency and Duration of 2000). contact, both deductively setting a priori rules Messaging on Impression and Relational Development 54. M. Ackerman, D. McDonald, Answer Garden 2: Merg- in Computer-Mediated Communication: An Explor- ing Organizational Memory with Collaborative Help and inductively watching which messages a atory Study (report presented at the Annual Confer- person takes first. (paper 97-105 presented at the Conference on Com- ence of the International Communication Associa- puter-Supported Cooperative Work, Cambridge, MA, An Internet year is like a dog year, tion, Washington, DC, 2001). December 1996). 24. J. Katz, Wired 1997 68, 76, 274 (December 1997). changing approximately seven times faster 55. O. Liechti, SIGGROUP Bull. 21, 3 (2000). 25. J. Katz, R. Rice, P. Aspden, Am. Behav. Sci., in press. 56. R. Fish, R. Kraut, R. Root, R. Rice, Commun. ACM 36, than normal human time. Nevertheless, I 26. C. Haythornthwaite, B. Wellman, J. Am. Soc. Inf. Sci. 48 (1993). 49, 1101 (1998). expect the transition from a group-based to 57. B. Buxton, Telepresence: Integrating Shared Task a networked society to continue (66). 27. B. Wellman, A. Q. Haase, J. Witte, K. Hampton, Am. Behav. Sci., in press. and Person Spaces, in proceedings of Graphics In- Although technology does not change 28. N. Nie, L. Erbing, Study Offers Early Look at How terface ’92, Vancouver, British Columbia, May society—it only affords possibilities for Internet Is Changing Daily Life (Institute for the 1992. 58. G. Moore, in Video-Mediated Communication, K. Finn, change—powerful forces are shaping the Quantitative Study of Social Science, Stanford, CA, 2000). A. J. Sellen, S. Wilbur, Eds. (Lawrence Erlbaum, Mah- Internet: increased broadband use, global 29. R. Kraut et al., Am. Psychol. 53, 1017 (1998). wah, NJ, 1997), pp. 301–321. ubiquity, portability, 24/7 availability, per- 30. P. DiMaggio, E. Hargittai, N. Russell, J. Robinson, 59. E. Bradner, W. Kellogg, T. Erickson, Social Affordances sonalization, and the switch from place-to- Annu. Rev. Sociol. 27, 207 (2001). of BABBLE (paper presented at the European Com- 31. C. Haythornthwaite, B. Wellman, Eds., special issue puter-Supported Cooperative Work Conference, place to person-to-person connectivity. on the Internet in everyday life, Am. Behav. Sci.,in Copenhagen, Denmark, November 1998). These suggest the accelerating need for press. 60. J. Boissevain, Friends of Friends: Networks, Manipula- social network concepts and tools for en- 32. B. Wellman, C. Haythornthwaite, Eds., The Internet in tors, and Coalitions (Blackwell, Oxford, 1974). 61. M. Kochen, Ed. The Small World (Ablex, Norwood, NJ, gaging with the Internet. Everyday Life (Blackwell, Oxford, in press). 33. R. Kraut et al., Internet Paradox Revisited (Carnegie 1989). Mellon University, 2001). 62. D. J. Watts, Small Worlds (Princeton Univ. Press, References and Notes 34. R. LaRosa, M. S. Eastin, J. Gregg, J. Online Behav. 1 Princeton, NJ, 1999). 1. The key HCI conferences are sponsored by the Asso- (2001) (see www.behavior.net/job/v1n2/paradox. 63. W. Sack, Mapping Conversations: Position Paper for ciation for Computing Machinery. They are SIGCHI html). the CSCW Workshop Dealing with Community Data (Special Interest Group on Computer-Human Inter- 35. P. Howard, L. Rainie, S. Jones, Am. Behav. Sci., in press. [paper presented at the Computer-Supported Coop- faces), SIGGROUP (groupware and group processes), 36. B. Anderson, K. Tracey, Am. Behav. Sci., in press. erative Work Conference (CSCW 2000), Philadelphia, and CSCW (Computer-Supported Cooperative Work). 37. J. Dimmick, C. J. Gade, C. Rankin, A Niche of Microdi- PA, December, 2000]. 2. M. A. Smith, personal communication. mension Analysis of Displacement of Long Distance 64. Q. Jones, G. Ravid, S. Rafaeli, Information Overload 3. M. A. Smith, in Communities in Cyberspace,M.A. Phone Use by E-Mail (paper presented at the Inter- and Virtual Public Discourse Boundaries (paper presented at CSCW 2000, Philadelphia, PA, December, Smith, P. Kollock, Eds. (Routledge, London, 1999), pp. national Communications Association Annual Meet- 2000). 195–219. ing, Washington, DC, 2001). 38. K. Hampton, B. Wellman, Am. Behav. Sci., in press. 65. N. Contractor, D. Zink, M. Chan, in Community Com- 4. M. Dodge, R. Kitchin, Mapping Cyberspace (Rout- 39. R. Ling, B. Yttri, in Perpetual Contact, J. Katz, M. puting and Support Systems, Lecture Notes in Com- ledge, London, 2001). Aakhus, Eds. (Cambridge Univ. Press, Cambridge, in puter Science, T. Ishida, Ed. (Springer-Verlag, Berlin, 5. S. Southwick, Liszt: Searchable Directory of E-Mail press). 1998), pp. 201–217. Discussion Groups (report to BlueMarble Information 40. K. Hampton, B. Wellman, City and Community,in 66. M. Castells, The Rise of the Network Society (Black- Services, Bloomington, IN, 1996). press. well, Malden, MA, ed. 2, 2000). 6. B. Wellman, in Culture of the Internet, S. Kiesler, Ed. 41. K. Hampton, thesis, University of Toronto (2001). 67. Research underlying this article has been supported (Lawrence Erlbaum, Mahwah, NJ, 1997), pp. 179–205. 42. P. Resnick, Who’s That? Connecting Neighbors by the Bell University Laboratories, Communications 7. B. Wellman, in Networks in the Global Village,B. through Directories and Distribution Lists (paper pre- and Information Technology Ontario, Mitel Net- Wellman, Ed. ( Westview Press, Boulder, CO, 1999), sented at CHI’99 Conference, Seattle, WA, May works, the Ofﬁce of Learning Technologies (Human pp. 1–47. 1999). Resources and Development Canada), the Social Sci- 8. M. Castells, The Rise of the Network Society (Black- 43. S. J. Ball-Rokeach,Y.-C. Kim, S. Matei, Commun. Res. ence and Humanities Research Council of Canada, well, Malden, MA, ed. 2, 2000). 28, 429 (2001). and at the University of Toronto: our NetLab at the 9. B. Wellman, Int. J. Urban Reg. Res. 25, 227 (2001). 44. C. Fischer, America Calling: A Social History of the Centre for Urban and Community Studies, Depart- 10. B. Wellman, M. Gulia, in Networks in the Global Telephone to 1940 (Univ. of California Press, Berke- ment of Sociology, and the Knowledge Media Design Village, B. Wellman, Ed. ( Westview Press, Boulder, ley, CA, 1992). Institute. Discussions with NetLab colleagues have CO, 1999), pp. 167–194. 45. N. Nie, L. Erbing, Study Offers Early Look at How been invaluable, especially J. Boase, W. Chen, K. 11. C. Stoll, Silicon Snake Oil: Second Thoughts on the Internet Is Changing Daily Life (Stanford University, Hampton, C. Haythornthwait, A. Q. Haase, J. Salaff, Information Highway (Doubleday, New York, 2000; www.stanford.edu/groups/siqss/Press_release. and B. Wellman. M. Prijatelj and U. Quach provided 1995). html). valuable assistance.

2034 14 SEPTEMBER 2001 VOL 293 SCIENCE www.sciencemag.org