Aatish Kumar
Computer Basic SC classes & Computer Education A&S Plaza Near Tehsil Road Doiwala Dehradun 8650928181 SC classes &Computer Education 1june 2018
Computer is an electronic machine which can store retrieves and process data can be programme with instruction .A computer of combination of hardware and software and can exit a variety of sizes and configuration.
The term hardware refers to the physical component of your computer such as the system unit CPU,MOUSE,etc. The software is the instruction that makes the computer work software is held either on your computer hard disk, CD ROM, DVD or in floppy disk.
Two type of computer 1. Mini computer 2. Mainframe computer These computers are very powerful used by large organization such as bank to control the entire business.
Cheap and easy to use often use and stand alone computer and in a network may be connected to the large mainframe computer with in big companies .
1. Input Device = keyboard ,mouse ,joysticks and game pad 2. Output Device = monitor ,printer ,speaker etc. Characterstics of computers 1. Speed A computer are very Fast machince a powerful computer capable of thousand of simple instruction in per second . 2. Accuracy In addition to being fast computer are also accurate. A computer cannot occur and error while performing any t 3. Diligence Computer is highly consistence they do not suffer from human tritons of bordem and tiredness resulting in lack of concentration computer are better than human being in performing any task.
4. Versatility Computer are versatility machine and are capable of performing any task as long as it can be broken down into a series of logical steps. 5. Storage capacity Computer can store large amount of data at a time a piece of information once record in a computer can never be forgotten and can be retrieve any time.
Reliability Consistency Versatile Communication Storage large amount data Fast processing speed Output can be produced in several
Ctrl+C=Copy Ctrl+V=Past Ctrl+A=Select all Ctrl+S=Save
Ctrl+X=Cut Ctrl+Z=Undo Ctrl+Y=Redo Ctrl+U=Underline Ctrl+I=Italic Ctrl+O=Open the file Ctrl+N=Open new file Ctrl+H=Replace Ctrl+K=Hyperlink
Ctrl+B=Bold Ctrl+F=Find F5=Refresh window F1=Help
F2=Rename the file Ctrl+P=For print Alt+Enter=Document property Ctrl+Shift+ESC=Task manager
Alt+F=File menu
First Generatiuon=(1945-1956) ENTAC=Electronic Numerical Integrator and Calculate EDVAC=Electronic Disecrete Variable Automatic Computer =1950 EDSAC=Electronic Delay Store Automatic Computer (1949)
UNIVAC=Universal Automatic computer
Disadvantage They emitted large amount of heat because they we They were too bulky of vacuum tube Air conditioning were required They were unreliable They were not portable
In the second generation transistor were used in place of vacuum tubes transistor are more compact than vaccum Type they made up of semi-conductors they are more durable than vacuum tubes. IBM=1620 (scientific purpose)
IBM=1401 (Business application ) CDC=3600 (Scientific purpose)
They were smaller than first generation computer They were generation less heat They took less computer time They were less prone failure
Disadvantage They were require AC They required frequently maintenance They were difficult and quite expansion
Single ICS has many transistor
These ICS are more compact then a transistor Resistor many transistor and capitol place on a single then of a silicon. IBM -360 –IBM -1964 PDP -8 – Dec -1965 POP -11 –Dec – 1970
They were smaller in size They generated less heart They involve low maintenance cost They were easily portable They were cheaper
These are used very large integration technology.
VLSI- After the introduction of integrated circuit computer would only gets in size hundreds of computer would fit an to one chip but the use of VLSI technology had squeezed thousand of computer in one time .
ALU=Arithmetic Logic Unit AMD=Advanced Micro Device ASCII=American Standard Code for Information Interchange AT=Advance Tecnology BIOS=Basic Input Output System CD=Compact Disk CDR=Compact Disk record
CDRW=Compact Disk Rewriter CD-ROM=Compact Disk Read Only Memory CPU=Central Processing Unit DDR=Double Data Rate
D-RAM=Dynamic Random Access Memory DVD=Digital Versatile Disk DVD-RAM=Digital Versatile Disk Random Access Memory ECC=Error Correction Code EEPROM=Electrically Erasable Programmable Read Only Memory EPROM=Erasable Programmable Read Only Memory FDD=Floppy Disk Drive GB=Giga Bytes GBPS=Giga Bytes per Second GHZ=Giga Hertz HDD=Hard Disk Drive
IBM=Interaction Business Mechanic Cooperation IC=Integrate Circuit ISO=interaction Standard organization KBPS=Kilo Bytes per Second
LAN=Local Area Network LCD=Liquid Crystal Display LED=Light Emitting Diode MAC=Media Excess Control MB=Mega Bytes MBPS=Mega Bytes per Second MHZ=Mega Hertz NIC=Network Interface Card PC=Personal Computer
RAM=Random Access Memory RDRAM=Rambus Dynamic Random Access Memory ROM=Read Only Memory
TB=Tara Bytes TBPS=Tetra Bytes per Second USB=Universal Serial Bus VCD=Video CD
WAN=Wide Area Network
SUM (value1:value2)=Days “Grade A” AVERAGE=(value1:value2) =Network DaysTRIM COUNT(value1:value2)CONCATENET TODAY( )=DATEVALUE MAX(value1:value2)=Grade=if (MO>=600,”GRADE) MIX (value: value2)