CS 008 UCR Chapter 1

computer

a programmable machine that converts raw data into useful information

General-purpose machines

most computers are _______ , meaning they can be programmed to do different things

Information Processing Cycle

process that converts data into information (input, processing, storage, output)

Joseph Marie Jacquard (19th c.)

-jacquard loom

-punched cards

-one of the first programmable machines

Charles Babbage (19th c.)

-Designed the analytical engine, a mechanical computer

-had all the basic components of modern day computers

-never completed.. technology of the time was too limited

Ada Lovelace (19th c.)

-created programs (on punched cards for Analytical Engine)

considered to be the first programmer

Alan Turing (20th c.)

-father of AI (artificial intelligence)

-turning test

-helped break Nazi communication codes during WW2

Grace Hopper (20th c.)

-accidentally coined the term "computer bug"

-created first compilers

First Generation Computers (1940s)

- used vacuum tubes to store and process data

- were massive in size

- not reliable

- programming done by manipulating switches

- ENIAC: first working digital, general purpose electronic computer

- UNIVAC: first commercially available computer, famously predicted outcome of 1952 presidential election

Second Generation Computers (1950s)

- used transistors to process data

- faster, smaller, more reliable, and cheaper than 1st gen. computers

Third Generation Computers (1960s)

- used integrated circuits (computer chips) that contained large numbers and transistors to process data

- faster, smaller, more reliable and cheaper than 2nd gen. computers

Fourth Generation Computers (1970s)

- an extension of the third generation

- first microprocessors developed were as powerful as the ENIAC

- had a central processing unit

- faster, smaller, more reliable and cheaper than 3rd gen. computers

Microprocessor

a complex integrated circuit that contains processing circuitry

Central Processing Unit (CPU)

the main processor in a computer

Moore's Law

- predicted that the number of transistors that could be placed on a computer chip would double every 2 years for at least a decade

- (actual pace closer to 18 months)

- pace held up until 2016 (50 yrs), not just a decade

- more transistors on a chip -> faster and more powerful the chip is

Binary Number System (Base-2 Number System)

computers use transistors and switches, which allow for 2 possible values and a transistor can either hold electricity (1) or not (0)- only two possible values

all data entered into a computer must be converted into _________ (binary digits)

Bits (numbers, characters, images, audio, video)

Bit (binary digit)

- smallest unit of digital data

- equates to a single transistor on a comp. chip

- can only have 2 values (1 or 0)

____ bit is not very useful, but a string of bits can represent more values

single

2 bits = ____ values

3 bits = ____ values

8 bits = ____ values

(base 2 equation)

4

8

256

Byte

unit of measure that equals 8 bits

ASCII (American Standard Code for Information Interchange)

- to represent characters, each symbol (letter, digit, etc)

- developed for english, later expanded for similar "romance" languages

- uses 8 bits (1 byte) for each character

- cannot be used to represent other languages

Unicode

- uses 16 bits (2 bytes) for each character

- backwards compatible with ASCII

- developed in early 1990s to handle other languages

- universally adopted

Using a standard binary code like _____ is crucial for communication (if one comp sends data to another using a different binary code, it will not be understood )

Unicode

1 Kilobyte (K)

1,000 (1 thousand bytes)

1 Megabyte (M)

1,000,000 (1 million bytes)

1 Gigabyte (G)

1,000,000,000 (1 billion bytes)

1 Terabyte (T)

1,000,000,000,000 (1 trillion) bytes

1 Petabyte (P)

1,000,000,000,000,000 (1 quadrillion) bytes

_____ used to measure transfer rates (such as internet connection)

Bits

Personal Computers (PCs)

- desktop computers

- all in one

- notebook (laptop) computers

- subnotebook computers

- netbook computers

Desktop Computers

-fits into a workspace, such as a desk

- not portable

- offers more speed, power, and upgradability for lower cost

- all in one: integrated monitor and system unit

Notebook (laptop) Computers

- portable

- can be as powerful as desktop but more expensive

Personal Computer Operating Systems (3)

- Microsoft Windows

- Mac OSX

- Linux (chromebooks)

Mobile Devices

- portable handheld computers used for business and entertainment

- fastest growing segment of computers (in sales)

- smartphones (small computers that combine services)

- tablets (larger and more powerful than smartphones but not as powerful as desktop and notebook. Same OS as smart phone)

Multiuser Computers

- systems that allow multiple simultaneous users to connect to them

- much more powerful than personal computers

- advantages include centralized resources and security

Multiuser Computers (4 MUCs)

- client/server

- supercomputers

- MainFrame Computers/enterprise servers

- Midrange Computers/minicomputers

Client (MUC)

a computer or device that requests services from a server

Server (MUC)

a computer that provides services to and or share resources with client computers over a network

_____ & _____ from the basis of how networking and the internet works

server

client

Supercomputers (MUC)

- fastest, most expensive computers in the world

- can be a single comp or a group that works together

- preforms complex mathematical calculations

- usually found in major universities and research institutes

- speeds normally measured in petaflops (1 petaflop = one thousand million)

Mainframe Computers/Enterprise Servers (MUC)

- large, very fast computers primarily used by large organizations for critical applications and bulk data processing

- can have thousands of concurrent users

Midrange Computers/Minicomputers (MUC)

- computers that are more larger, powerful and expensive than desktop computers but smaller, less powerful and expensive than mainframe computers

- can have dozens or hundreds of concurrent users

- primarily used by medium sized companies

Ergonimics

- study of the relationship between workers and their work spaces

- jobs involving mostly computers can lead to health issues

Distributed Computing

- distributes the processing of a task across a group of computers

- with this, a group of less powerful computers can often perform same tasks as more powerful/expensive computers

Grid Computing

form of distributed computing using a group of computers in one location

Volunteer Computing

form of distributed computing that used computers from around the world

Ubiquitous Computing (invisible computing)

technology that recedes into the background and becomes apart of the environment

(is all around us but is so common we do not notice)

Embedded Compter

a specialized computer that is part of another device

(gas pumps, microwaves, traffic lights)

Internet of Things (IoT)

- connection of the physical world to the interned

(devices located, monitored and controlled by embedded computers)

Convergence

the integration of different technologies onto multifunction devices (one device can replace multiple)