1.01 Evolution of Programming Languages

glintplainvilleΛογισμικό & κατασκευή λογ/κού

18 Νοε 2013 (πριν από 3 χρόνια και 8 μήνες)

81 εμφανίσεις

1.01


Evolution of Programming Languages


I.


Categories of Programming Languages

A.

Low Level

1.

Characteristics

a)

Almost no abstraction from the hardware

b)

Code is written to specific hardware

c)

Code will only operate on the hardware for which it was written

2.

Examples

a)

Machine Code (1
st

Generation)

i.

Understood directly by CPU

ii.

Takes specialized knowledge to program

iii.

Uses hexadecimal numbering system

b)

Assembly Language

i.

One level of abstraction from machine code

ii.

MASM is an assembly language

B.

High Level

1.

Characteristics

a)

Strong
abstraction from the hardware

b)

Program can be written to run on many types of computers that run the same operating
system

2.

Examples

a)

Visual Basic 2010

i.

BASIC

(1964) was adapted by Microsoft for the purpose of writing Windows and Web
applications

ii.

VB was releas
ed in 1991

iii.

VB 2010 is the 9
th

version

iv.

Object
-
oriented programming language (OOP)

b)

Visual C#

i.

Created by Microsoft (2001)

ii.

Intended to be a simple, modern, general
-
purpose object
-
oriented programming language.

iii.

Current version is C# 4.0

iv.

Language most closely re
lated to CLI (Common Language Infrastructure)

backbone of the
.Net framework

c)

Other high level languages are C++, F#, Java, and many more

II.

History of Programming Languages

A.

First Computer Program

1.

Written by Ada Lovelac
e

2.

Written in 1842
-
43

B.

Modern Computer
Programming Languages

1.

1940s

Plankalk
ü
l

a)

W
ritten by Konrad Zuse

b)

Not implemented until 1998

2.

1950s and 1960s

a)

FORTRAN
(Formula Translation)

i.

1955




ii.

John Backus and others

b)

COBOL

(Common Business
-
Oriented Language)

i.

1959

ii.

Grace Hopper and others

iii.

Many of today’s
financial computer programs are written in COBOL

c)

RPG

(Report Program Generator)

i.

1950

ii.

IBM

d)

BASIC

(Beginners’ All
-
purpose Symbolic Instruction Code)

i.

1964

ii.

Was widely taught in secondary schools

3.

Late 1960s and 1970s

a)

B

i.

1969

ii.

Forerunner to C

b)

Pascal

i.

1970

ii.

Java borro
ws from Pascal

c)

C

i.

1972

ii.

C++, Java, C# and others are based on C

d)

ML

i.

1973

ii.

F# is based on ML

iii.

C++ borrows from ML


e)

SQL

i.

1978

ii.

Used for databases (Oracle, SAS)

4.

The Internet Age

1990s

a)

Python

1991

b)

Java

1995

c)

Javascript

1995 (not related to Java)

d)

PHP

1995

e)

Delphi

1995 (Object Pascal)

III.

Evolution of Computer Programming Languages

A.

Modern languages have more abstraction

1.

Java program can run on a Windows system on any computer as long as a Java compiler is
installed

2.

Early programs were hardware
-
specific

B.

Modern
languages have moved to Object Oriented Programming (OOP)




1.

Use objects

data structures consisting of data fields and methods to design applications and
computer programs

2.

Early programming languages did NOT use OOP