Friday, March 27, 2015

BLASTS FROM THE PAST. (Computer History from 50,000 BCE To 2008)

50,000 - 20,000 BCE
Pebbles and human fingers are the first tools for calculation. The Latin word digit means finger
(or toe) as well as a number, and the Latin word for pebbles is calculus, giving us the word "calculate"

20,000 BCE
The oldest-known objects used to represent numbers are bones with carved notches

c 2400 BCE
The abacus - the first known calculator - is invented in Babylonia





c 500-300 BCE
Ancient Indian writer Pingala describes the first binary(two digit code) numbering system

87 BCE
A mechanical computer used to predict the movement of stars is built. It is discovered in a shipwreck off the coast of the Greek island of the Geek island of Antikythera in 1901

Front panel of a 2007 reproduction

724 CE
Chinese engineer Liang Ling-Can builds the first mechanical clock (driven by water) parts that make a ticking sound. More than 1,300 years later, early computers and robots inherit the technology from

Computer Anatomy (Monitor, Keyboard, Mouse, CPU, Hard Disk, Motherboard, RAM, ROM, Ports) , Data Storage History and Geek Speak (program)


Monitor
LCD screen displays text and images made up to individual dots of color called pixel.

Keyboard

contains microprocessor that detects which key has been pressed and sends a signal to the control processing unit.

Mouse
As the mouse is moved it sends co-ordinates to the computer, which moves the cursor on the screen.

CPU
the central processing unit is the brains of the

Wednesday, March 25, 2015

Internet Pioneer : Tim Berners-Lee

British scientist Tim Berners-Lee (Born: June 8, 1955 (age 59), London, United Kingdom) invented a simple computer language (HTML) that allowed pages to be linked together and designed an addressing scheme (URL) to locate each page. He then created the first web browser to allow peop;e to access his creation, the World Wide Web, making all the resources of the Internet availbale to everyone in the world.

Sir Timothy John "Tim" Berners-Lee, OM, KBE, FRS, FREng, FRSA, DFBCS, also known as

Blast From The Past. (Computer)

1969
DIstant computers first commucicate with each other when Arpanet is set up, linking computers at four US universities.

1971
The first email message is sent between computers.

1983
A new computer language called TCP/IP allows all computers on the network t communicate with each other. The network is called the Internet and governments and universities begin to use it.

1991
The World Wide Web is created, giving people a simple way to navigate throung the information on the Internet.

2008
There are more than 100 million websites.



Name Game (Domain Names)

Top domain names (the letters after the dot at the end of a website address) work like international phone numbers, grouping websites.

.aero      aviation industry
.biz        business
.com      commercial
.edu       educational (US)
.gov       government
.info      general information
.int        international organization
.mil       US military
.net       major service provider
.org       non-profit organization




How to: set up a search engine

  1. Develop a "web spider" - a software program to browse the Internet.
  2. Instruct the spider to begin its "web crawl" at popular websites, building an index of the words on the pages.
  3. By following the links on the sites, the spider will quickly spread out across much of the web.
  4. Build up an index of search words found by the spider and encode and store the data for users to access.
  5. Develop search engine software - a program to sift through the millions of

Where is the Internet?


The Internet is everywhere. It's a network linking millions of computers all over the world. With a computer, the right software and a phone connection, anyone anywhere in the world can set up a website for anyone else to look at.


There's no one in charge of the Internet and since there's no limit to the number of computers that can be linked, there's no limit to the amount of information that can be held on it.


Four Incredible Internet Facts 
  1. The first message sent between computers was "lo". The sender was trying to

How do computer store data ?

All the data stored in computer - every word, picture, number and sound - is captured as a series of electrical pulses that are either on or off. A number system called binary is used to represent these pulses with "1" meaning "on" and "0" meaning "off".

A single binary digit, known as a "bit", switches a single switch on or off. By linking together these switches, the computer can carry out the complex operations we demand.

Bits and bytes

1 bit = a binary digit either 1 (on) or 0 (off).
1 byte = 8 bits
1 kilobyte =