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Evolution of Computers
and Programming Languages
COMPUTER PROGRAMMING I

Evolution of Computers
COMPUTER PROGRAMMING I

Mechanical Devices
● Pascaline (1642)
○ Set of gears, similar to clock
○ Only performed addition

● Stepped Reckoner
○ Gottfried Leibniz
○ Cylindrical wheel with movable
carriage
○ Add, subtract, multiply, divide,
square roots
○ Jammed/malfunctioned

Mechanical Devices
● Difference Machine (1822)
○ Charles Babbage
○ Produce table of numbers used
by ships’ navigators
...

● Ada Byron
○ Sponsor of Analytical Machine
○ One of first people to realize its
power and significance
○ Often called the first programmer
because she wrote a program based on the design of the
Analytical Machine
...

○ Highly sophisticated calculator - unreliable

The Mark 1

Electro-Mechanical Devices
● These devices were not mass produced
...

● Mark 1 – 51 ft
...


● ENIAC
○
○
○

○

Electronic Numerical Integration and Calculator
1943, 30 tons, 1500 sq ft
...

Solve a problem in 20 min that would have take a
team of mathematicians three days to solve
...


The Stored Program Computer
● Alan Turing & John von Neumann
○ Mathematicians with the idea of stored programs
● Turing
○ Developed idea of “universal machine”
○ Perform many different tasks by changing a program (list of
instructions)
● Von Neumann
○ Presented idea of stored program concept
○ The stored program computer would store computer
instructions in a CPU
...

•

Machine language (1’s & 0’s)

The Stored Program Computer
● Mauchly & Eckert built 3rd computer (UNIVAC -

UNIVersal Automatic Computer)
○
○
○

1st computer language – C-10 (developed by Betty Holberton)
Holberton also developed first keyboard and numeric keypad
First UNIVAC sold to US Census Bureau in 1951

Second Generation Computers
● 1947, Bell Lab (Shockley, Bardeen, Brittain)
○ Invented the transistor
•
•

Replaced many vacuum tubes
Less expensive, increased
calculating speeds

● Model 650 (early 1960s)
○ IBM introduced first
medium-sized
computer (Model 650)
○ Still expensive

Second Generation Computers
● Change in way data was stored
● Magnetic tape and high speed

reel-to-reel tape machines
replaced punched cards
● Magnetic tape gave computers

ability to read (access) and write
(store) data quickly and reliably

Third Generation Computers
● Integrated circuits (ICs) – replaced transistors
○ Kilby and Noyce – working independently developed the IC
(chip)
● ICs
○ Silicon wafers with intricate circuits etched in their surfaces
and then coated with a metallic oxide that fills in the etched
circuit patterns
● IBM System 360 (1964)
○ One of first computers to use IC

Mainframes
● A large computer that is usually

used for multi-user applications
● IBM System 360 one of first

mainframes
● Used terminals to communicate

with mainframe

Fourth Generation Computer
● Microprocessor (1970)
○ Hoff at Intel Corp, invented microprocessor
○ Entire CPU on a chip
○ Makes possible to build the microcomputer (or PC)
○ Altair – one of first PCs 1975
○ Wozniak and Jobs designed and build first Apple Computer in
1976
○ IBM introduced IBM-PC in 1981

Components of a Computer
COMPUTER PROGRAMMING 1

Components of the Computer
1
...

3
...

5
...


○

Designed to fit on or under a desk
...

Use stylus for input

Smart phones
•

•

Cellular phones that are able to read and receive email and access
the Internet
Some have cameras, video, mp3 players

Desktop and Mobile Computing
● Mobile computing devices
○ Wearable computer
•

•
•

Designed to be worn
• In clothing
• Wristband
MP3 players, hands-free cell phones
Monitor health problems

The Personal Computer
● Base Unit
○ Contains many storage devices such as a diskette drive, a
cd/dvd drive, and a hard disk drive
...

ALU (Arithmetic Logic Unit)
• Performs logic and arithmetic operations
• Makes comparisons
• So fast that the time need to carry out a single addition is
measured in nanoseconds (billionths of a second)

CPU/Processor
● A computer’s processor is the “brain” of the

computer
...

○

Speed is measured in Hz usually gigahertz (GHz) today
...

•

Current CPUs range from 1
...
6GHz
...

○

CPUs now have up to 8 “brains”
...
The operation could change
very rapidly, but it always only actually performing one
operation
...


Data Flow through the CPU

Input

Memory

CPU

The “Brain” of the
Computer

Output

CPU
● CPUs contains the following:
○
○
○
○
○

L1 cache
L2 cache
Processing Unit
Memory Controller
Cache is high speed memory that stores frequently accessed
instructions
...
Current CPUs
have 1 MB of L1 cache and up to 32MB of L2 cache
...


L(Level) 1 cache is within the CPU itself
...

○

Example: If you are playing a card game, the L1 cache might
store the instruction to flip over a new card
...


Cache
● Level 2 cache is at the top of each die
...
L1 cache is located at the bottom middle
...
Intel Q6600 to be
exact
...
This

board is where all components of your computer
are plugged into
...
(sound and video) **2005
• Clock rate
• Determines the speed at which a CPU can execute instructions
• Megahertz (million of cycles per second) MHz
• Gigahertz (billion of cycles per second)GHz
•

Memory
• Stores data electronically
• ROM – Read Only Memory
• Contains most basic operating instructions for computer
• Cannot be changed – permanent
•

RAM – Random Access Memory
• Memory where data and instructions are stored temporarily
• Data stored in RAM can be written to any type of storage media
(diskette, cd, jump drive)

The Motherboard
○

Contains
•

•

•

•

SRAM – Static Random Access Memory
• High-speed memory referred to as cache
• Used to store frequently used data for quick retrieval
Bus
• Set of circuits that connect the CPU to other components
Data Bus/Address Bus
• Transfers data between the CPU, memory and other hardware
addresses that indicate where the data is located and where it
should go
Control Bus
• Carries control signals

Random Access Memory (RAM)
● Without RAM your computer will not operate
...

○

RAM is plugged into the motherboard into the long slots with
tabs on the end
...


A stick of RAM →

RAM
● RAM holds data for all applications that are

currently running on your computer, but only while
the power is on
...


Types of RAM
● Current computers use DDR2 or DDR3 RAM
...

● DDR= Double Data Rate which means the computer

reads data from the RAM at least two times per cycle
...


DDR2-800 and PC2-6400 are the same thing
...


○

Throughput is measured in MB/sec so 6400=6400MB/sec or
6
...


○

PC2- DDR2 PC3- DDR3

Bytes
● The unit used to measure memory and storage on a

computer is a byte
...
A bit is a single 0 or 1 in binary
...

○

Some languages (mainly Asian) require 2 bytes to display one
character
...
Kilobyte, Megabyte etc
...
(KB, MB, GB)
...

○

Why is this?

Wrong Numbers?
● The numbers you just saw are all in fact wrong- at

least when it comes to a computer
...

1 MB is actually 1,024KB
...


Storage
● Data can be permanently stored on various devices
...


Hard Drive
● Works much like a record player
...


Hard drive with cover off
showing a platter and the
read/write arm
...
The data is read using a laser
...
CDs

hold around 700MB of data, DVDs hold up to 15
...


More Optical
● CDs and DVDs can be different types○
○
○
○
○

Audio
Video
Data
Picture
The only difference is what
format the data is stored in
...


Flash Drives
● Flash drives are USB drives are sold in capacities of

128MB to 128GB
...


More Flash
● Unlike other storage- flash drives can be dropped and not

lose data
...


Programming Languages
COMPUTER PROGRAMMING I

Types of Languages
● Programming languages were created to give

instruction
...

○

If a language has higher abstraction – it is further away from
machine language (1’s and 0’s)

Low Level
● Low level languages have almost no abstraction

from the hardware
...


More Low Level
● Two types:
○

Machine Code (1GL)

○

Assembly Language (2GL)

Machine Code
● Machine code is understood directly by the CPU
...

● What numbering system is this?

Machine Code
● 8B542408 83FA0077 06B80000 0000C383

FA027706 B8010000 00C353BB 01000000
B9010000 008D0419 83FA0376 078BD98B
C84AEBF1 5BC3
● If you said Hex, you are right! Machine code is

written in hex
...


Assembly Language
● One level of

abstraction from
machine code is
assembly language
...


High Level Language
● In contrast a high level language provides strong

abstraction from the hardware
...


More High Level
● We will code in Visual Basic 2010
● Basic is an old language that has been updated over

the years and adapted by Microsoft for use for writing
Microsoft Windows and Web applications
...

● The current version of Visual Basic is the 9th version

from Microsoft
...
This moved the

BASIC language to an event driven and
object-oriented programming (OOP) language
...

● Modern programming is said to of started in the

1940s
...
It was designed by Konrad Zuse
...
(1955)

○

LISP- John McCarthy et al
...
(1959)

○

RPG- IBM (1959)

○

BASIC- 1964 (as noted previously)

Late 1960s and 1970s
● This was the period when most of the languages used

today were invented or are derived from one of the
languages invented in this time period
...

○

For example a program written in Java on a Windows system
an run on a Mac, Windows, Linux, etc
...


● Early programs were bound to specific hardware-

current programs are not
...

● As defined by Wikipedia:

Object-oriented programming (OOP) is a
programming paradigm using "objects" – data
structures consisting of data fields and methods
together with their interactions – to design
applications and computer programs
...




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