CST 1100 Section 2304
Introduction to Computers
Chapter 1
Computers
Calculations
Media
Entertainment
Personal
Home Appliances
Computers are beneficial
“ETHICS”
Harmful
- Privacy
Layers of a computer
Computers are made of different components
- Information
o Hardware
 Software/programs
 Operating system
o Communication
Information
Can be anything – at the very core, all information is converted to zeros and ones ->
binary
Early “Computers”
- Initially for calculating
- Pyramids
- Stone Henge
- Abacus
17th Century (1600s)
- First adding subtracting machine was invented
- Gears that moved
- Performed whole number addition + subtraction
19th Century (1800s)
- Charles Babbage designed an analytical engine
- This engine was so advanced it is thought to be the original computer
- He never built it because technology was not there at the time, he just designed it
but could not implement it
- It has 8000 parts
In the late 19th Century (1800s)
- William Burroughs – produced & sold a mechanical adding machine
Beginning of the 1900s
- Dr. Herman Hollerith developed the first electrical mechanical tabulator
o Read information from punched card
o Started IBM
In 1936
Alan Turing invented an abstract mathematical model called the Turing Machine
- Read/write device
- Scanned for zeros & ones
WWII
First full scale computer was invented & marketed during this time
- Eniac
- Harvard Mark I
First commercial computer
- UNIVAC
- The first people to use the UNIVAC were the people at the Census Bureau
First generation (1951-1959)
1. Computers were built for commercial use
2. Computers used vacuum tubes
o Generated a lot of heat
o Not reliable
o Required air conditioning so it would not overheat
3. Memory used in these early computers were magnetic drums
4. Input devices were card readers
5. Output devices were punched cards or line printers
6. By end of this era magnetic drums were replaced by magnetic tape
Second generation (1959-1965)
1. Transistors replaced the vacuum tubes
o Smaller, More reliable, Faster, Cheaper
2. Magnetic disks
3. Magnetic core was used for storage
Third generation (1965-1971)
1. Development of integrated circuits (IC)
o Solid pieces of silicon that contained transistors & connections & other
components
o Smaller , cheaper, faster, more reliable than transistors
Fourth generation (1971 ->)
1. Personal Computers
2. Apple Computers
3. Companies other than IBM came into being -> Dell, Sun, Compaq
4. RISC were developed
5. UNIX
6. Parallel computing
7. Networking – Ethernet(1973)
8. Intel Chip (1985)
9. Novell (1989)
10. Internet (1990s)
11. Monitors
Software History
First Generation (1951 -1959)
1. Programs were written in machine code
2. Machine code is hardwired into the computer – built on the electronic circuits of
computers
3. Expert s for machine code
4. Then towards the end of the era, Assembler(use of mnemonics)
o ADD => mnenomics
Second Generation (1959-1965)
- More powerful languages
o Fortran
o Cobol
o LISP
Third Generation (1965-1971)
1. Better operating systems was developed
2. Statistical programs – SPSS
Fourth Generation (1971-1989)
1. More OS
o UNIX
o PC DOS
o MSDOS
2. MAC introduced the mouse
3. Office Software
o WORDSTAR
o WORDPERFECT
o LOTUS 1-2-3
o dBASEIII
Fifth Generation (1989 ->)
Microsoft
- Word
- Excel
- Access
- Power Point
Java, Visual
Internet, www
Chapter 2 – Binary values and number systems
-
Computers -> number are crucial specifically zero & ones
Computers store everything in zero and ones
Number
o A unit belonging to an abstract mathematical system
o Is subject to certain laws of addition, multiplication and succession
o Numbers have categories
 Natural numbers – zero and any # obtained by repeatedly adding
one to the number
 Negative numbers – number less than zero & have the opposite
sign of positive number
 Integers – any natural & negative numbers
 Rational – is an integer or the quotient of two integers – any value
that can be expressed as a fraction
o BASE OF A NUMBER
 The base of a number is the number of digit used in the system
 For example.
 BASE 10 has 10 digits -> 0,1,2,3,4,5,6,7,8,9
 BASE 2 has 2 digits -> 0,1 (Most important, Binary)
 BASE 8 has 8 digits -> 0,1,2,3,4,5,6,7
 BASE 16 has 16 digits -> 0,1,2,3,4,5,6,7,8,9,A,B,C,D,E,F
(HEX)
 11 in BASE 10 is different than 11 in BASE 2 & 8