History of UNIX 1969 Created at AT&T Bell Labs, Massachusetts Institute of Technology Researchers: Ken Thompson, Dennis Ritchie, M. D. Mcllroy, Joe Ossana Based on experimental remote-access, time-shared operating system, Multics 1970s Unix was rewritten in the C programming language in 1972. First Unix development support group formed in Bell Labs in 1973. UNIX philosophy emerges. AT&T began licensing Unix to universities, commercial companies and the US government. Bill Joy produces first Berkeley Software Distribution(BSD) of Unix in 1978 1980s In 1983, AT&T began to commercialize Unix. BSD Unix became popular as alternative to AT&T’s Unix System V. Standardization of Unix attempts begins with the X/Open consortium. Start of the “UNIX Wars”. Open Software Foundation and UNIX International founded in 1988. 1990s In 1993, “Unix Wars” end with merger of Unix International and Open Software Foundation. Novell buys UNIX System Laboratories from AT&T Also in 1993, Novell transfers Unix trademark and rights to X/Open Consortium X/Open Consortium merges with Open Software Foundation to form the Open Group in 1996. 1990s (cont.) Novell sold admin and support business to Santa Cruz Operation along with development rights in 1995. Apple Computers acquired BSD based operating system, NEXTSTEP in 1997. Renamed Darwin. 2000s Dot Com bubble(2001-2003) burst triggered significant consolidation of versions of Unix. Santa Cruz Operations started legal action against Linux in 2003 resulting in SCO vs Novell lawsuit. On August 10, 2007, Novell won majority of lawsuit. SCO appealed. Modern Uses of Unix Unix trademark defined by the Single UNIX Specification. Operating Systems that do no meet the Single UNIX Specification are called Unix-like. The three current dominant Unix-like systems: GNU/Linux BSD Solaris Linux Increasing popularity in desktop computers GUI (GNOME and KDE) Dedicated effort to improve performance on desktops Many popular applications have a Linux version Dominant OS in top server environments LAMP package 459 out of the top 500 supercomputers are running Linux Linux (cont.) Embedded systems Cell phones and PDA Routers and hardware firewalls BSD Mac OS X is built on a BSD Kernel called Darwin. Most popular Network Attached Storage(NAS) OS is FreeNAS which is based on FreeBSD. References http://en.wikipedia.org/wiki/Unix http://en.wikipedia.org/wiki/Linux http://www.unix.org/what_is_unix/history_timeline.html http://www.computerhope.com/history/unix.htm Basic components of Computer Cho Ko San - DipIT8 - 0825 Four Main Functions Input Process Output Storage INPUT PROCESS OUTPUT STORAGE Cho Ko San - DipIT8 - 0825 Input / Output Input: the process of entering raw data to computer Output: the process of producing useful information resulted from the computer’s operation Variety of peripheral devices used for input / output are: à Input devices: Keyboard, Joystick, Mouse, Scanner, Microphones , barcode readers, video camera, digital camera, magnetic stripe card, POS devices... Etc. à Output devices: Monitor, Speaker, Printer, LCD .. Etc. Cho Ko San - DipIT8 - 0825 Data What is Data? - Raw facts - Can be in any formats, such as text & numeric, code, picture, song/video files, coding, instructions.. etc - Can be Human-readable or Machine-readable - To be understandable by Computers, data must be converted from human-readable format into machine-readable format. Cho Ko San - DipIT8 - 0825 Process Computer takes data through input devices. Every actions on or by the input devices are converted into electromagnetic signals. These signals are sent to Signal Processing Unit, which converts the analog into digital and transfers it directly to processor or to processor via memory for further processing. Cho Ko San - DipIT8 - 0825 Process CPU (Micro Processor) – Central Processing Unit Speed measure in Clock speed - Hertz (Megahertz, Gigahertz) Two types: à CU (Control Unit) - not execute the program - accesses program instructions, decodes them and coordinates the flow of data in and out of ALU or other storage. à ALU (Arithmetic/Logic Unit) - execute all arithmetic & logical operations Cho Ko San - DipIT8 - 0825 Process Before the instructions can be executed, instructions and data are kept in the temporary or primary storage from an input device or secondary storage device. There are 4 steps to perform: ◦ The control unit fetches (gets) the instruction from memory. ◦ The control unit decodes the instruction (decides what it means) and directs that the necessary data be moved from memory to the arithmetic/logic unit. These first two steps together are called instruction time, or I-time. (by CU) ◦ The arithmetic/logic unit executes the arithmetic or logical instruction. That is, the ALU is given control and performs the actual operation on the data. ◦ The arithmetic/logic unit stores the result of this operation in memory or in a register. Steps 3 and 4 together are called execution time, or E-time. (by ALU) Cho Ko San - DipIT8 - 0825 Process Register - Part of the CPU - Temporary storage areas of instructions or data - Work under the direction of the control unit to accept, hold and transfer data or instruction. Different types of registers: à An accumulator – collect the result of computations à An address register – keep track of where data or instruction is stored in memory à A storage register – temporarily holds data à A general-purpose register – used for several functions Cho Ko San - DipIT8 - 0825 Storage Two basic categories: Short-Term (Primary) & Long Term (Secondary) à Primary Storage drive (work closely with CPU) - ROM (Read Only Memory - Non-Volatile) - RAM (Random access Memory - Volatile) - Cache Memory à Secondary Storage drive - Hard Disk Drive (HDD) Hardware outside computer – Memory Stick (USB drive), Floppy Disk, CD, DVD, Magnetic Tape, .. Etc. Cho Ko San - DipIT8 - 0825 Reference: Books: Fundamentals of Information System (Fourth Edition) Author: Ralph Stair . George Reynolds http://homepage.cs.uri.edu/faculty/wolfe/book/Readings/Reading04.htm http://www.pantherproducts.co.uk/Articles/CPU/CPU%20cache.htm Thank you Cho Ko San - DipIT8 - 0825 NOW YOU SEE IT, NOW YOU DON’T! {hidden computers} {by Victoria Yim} WHAT ARE HIDDEN COMPUTERS? Different computers which we interact with in our every day life… ¢ Microwaves ¢ Cameras ¢ Cell phones ¢ ATM’s ¢ Electronic Calculators ¢ MP3/MP4/Ipod touch ¢ MRT gentry ¢ PSP ¢ Security Cameras ¢ Elevators LET’S TAKE A CLOSER LOOK AT THE ELEVATORS WHAT IS AN ELEVATOR?? An elevator is a device that moves things or people from one level to another. They are extremely important for tall buildings…or basically any building that have more than four levels. …by the way, they are also important for old people- or people with bad knees-or handicap people… A LOOK AT THE ELEVATOR’S HISTORY ¢ primitive elevators were used as early as the 3rd century BC ¢ they were operated by humans, animals or water wheel power ¢ by the mid 19th century, power elevators which were often steam-operated were used for conveying materials in the mines, factories, etc. ¢ in 1853, an American inventor by the name of Elisha Otis introduced a freight elevator equipped with a safety device to prevent it from falling in case the cable snapped. ¢ the electric elevator came into the picture towards the end of the 19th century. ¢ it was built by a German inventor named Werner von Siemens in 1880. HOW DO ELECTRIC ELEVATORS WORK? ¢ Most modern computers are controlled by computers ¢ For the elevators to work, the computer needs to know three things: ¢ where people wants to go ¢ where each floor is ¢ where the elevator car is ¢ The buttons on the elevator car and the buttons on each floor are wired to the computer, when you press a button, the computer logs the request. ¢ A common way to find out where is the car is by having the light sensor at the side of the car reads a series of holes in a long vertical shape in the shaft. ¢ The computer knows exactly where the car is in the shaft by counting the holes as it speeds by. ¢ An advance method is now used to ‘track’ the passengers’ traffic movements. They are able to know which levels have the highest demand at what time and are able to direct the elevator cars accordingly. INTERESTING ELEVATOR FACTS: ¢ Werner von Siemens, inventor of the first electric elevator is the founder of the electrical and telecommunications company Siemens. ¢ The fastest elevator is located in Taiwan in the Taipei 101 building. The elevator can carry passengers from the ground to the top in 30 seconds! That’s 1,010 meters per minute. ¢ Elevators are called lifts in England (and Singapore). REFERENCES ¢ http://inventors.about.com/library/inventors/ blelevator.htm ¢ http://www.answers.com/topic/how-do-elevators- work ¢ http://science.howstuffworks.com/transport/ engines-equipment/elevator7.htm ¢ http://www.forbes.com/2007/10/01/elevators- economics-construction-biz-logistics- cx_rm_tvr_1001elevators.html .