Module 7: History of the computer

Question 1

Evolution of computer hardware timeline

First gen

Second

Third

Fourth

Answer 1

1. First Gen: mid 40’s – late 50’s
2. Second Gen: 1959 – 1965
3. Third gen: 1965 – early 70’s
4. Fourth gen: 70’s – now

Question 2

First Generation

Answer 2

Special purpose machines designed to perform one type of computation

Classified by reliance on vaccum tubes, relay switches, and need to program in machine language

ENIAC was first digital, general purpose, programmable computer

Question 3

Second Generation

Answer 3

Used transistor components rather than vaccum tubes (reduced cost because they could be mass produced)

Transistors used less power and were more robust

Magnetic core memory was introduced which allowed for larger main memory size

Size of computer reduced

External storage moved from magnetic tape to disk drives/disk drums

Computers of this era were called mainframe computers

Question 4

Third Generation

Answer 4

Classified by use of silicon chips to replace transistors and magnetic core memory

Companies started producing “families” of computers that could run programs without having to alter code, which gave birth to the software development field.

Computer networks were introduced

Question 5

Fourth Generation

Answer 5

Classified by microprocessor

Allowed computer to be built around single chip making computers small enough to sit on a desk

Increased processor and memory capacities allowed graphics, word processing, and accounting software to be developed

Examples: Mark 8, Apple I

Question 6

Machine and Low Level Languages

Answer 6

1st gen was connecting memory locations to computational circuits with cable

Have to “rewire” entire computer to run next program

Question 7

Evolution of Programming: Language translators

Answer 7

Language translator is program that takes another program as input and outputs the machine language version

Earliest were known as assemblers, which translated assembly language to machine language.

Still required detailed, precise, low level instructions

Question 8

Evolution of Programming: High Level Languages

Answer 8

High level languages allowed programs to be written in more english like way

This class of language translator was known as a compiler

Question 9

First High Level Languages

Answer 9

Fortran (1959)

COBOL

LISP

Simula

SNOBOL

C (Developed in 1968)

Question 10

Evolution of Programming: Structured Programming

Answer 10

Used high level control construct such as while/for loops and “if-else’ statements while eliminating the problematic “GOTO” statements used in earlier laguages

Eg. C and Pascal

Question 11

Evolution of Programming: Object-Oriented Programming

Answer 11

Defines classes of entities called objects

Initially introduced in language “Smalltalk” in 70’s and early 80’s

In mid 80’s object-oriented capabilities were incorporated into new version of C called C++

Question 12

Compiled language vs. Interpreted Languages (scripting)

Answer 12

The code of a compiled program is more efficient but the process of development and testing is less efficient compared to interpreted language

Interpreted Languages: Programmer enters command, interpreter converts it to machine language and executes

Scripting languages include: Perl, php, ruby, python, and asp

Question 13

What factors contributed to the development of the first generation of computers

Answer 13

The need to easily calculate missle trajectories

Question 14

Generation when computers began to see wide-spread use in business

Answer 14

Third Generation

Question 15

What technology was introduced in the 4th generation of computers

Answer 15

Microprocessors

Question 16

First programming language to introduce Object Oriented Programming

Answer 16

Smalltalk

Question 17

Advantage of high level programming languages over low-level programming languages

Answer 17

Used english words