Docsity
Docsity

Prepare for your exams
Prepare for your exams

Study with the several resources on Docsity


Earn points to download
Earn points to download

Earn points by helping other students or get them with a premium plan


Guidelines and tips
Guidelines and tips

Hardware and Software - Introduction to Computer Science and Programming - Lecture S, Lecture notes of Computer Security

The key points in computer security which should be know as a beginner are given below:Hardware and Software, Physical Parts, Components and Peripherals, Hard Disk, Drive, Motherboard, Execute, Instructions, Microsoft Office, Firefox

Typology: Lecture notes

2012/2013

Uploaded on 04/22/2013

satheesh
satheesh 🇮🇳

4.5

(11)

90 documents

1 / 19

Toggle sidebar

This page cannot be seen from the preview

Don't miss anything!

bg1
Hardware and Software
Docsity.com
pf3
pf4
pf5
pf8
pf9
pfa
pfd
pfe
pff
pf12
pf13

Partial preview of the text

Download Hardware and Software - Introduction to Computer Science and Programming - Lecture S and more Lecture notes Computer Security in PDF only on Docsity!

Hardware and Software

Hardware

 Hardware refers to the physical parts of the

computer.

 (^) Hardware is sometimes referred to as computer components and peripherals.  (^) E.g., Motherboard, Hard Disk/Drive

 Software refers to the set(s) of instructions given to

the computer to execute one or more tasks.

 (^) Software is sometimes referred to as programs or applications.  (^) E.g., Microsoft Office, Firefox

Early Calculation 2/

In early 1800s, Jacquard used punched cards to control a loom.

Hollerith used punched cards for the 1890 US census (his company eventually became IBM!).

Babbage’s difference engine (1830) calculated tables of polynomial values.

Analogue Computing

Vannevar Bush (1930) built a differential analyzer that used wheels/discs to perform integration.

Babbage designed (but never built) the first general-purpose programmable computer – the analytical engine.

1960s to Present

First transistors and integrated circuits and finally

microprocessors, revolutionised computing, made them

small, cheaper and more general-purpose.

ZX80 (1980)

IBM PC (1980) Apple MAC (1985)

The Von Neumann Architecture

 (^) This describes how a conceptual computing device works:  (^) Memory stores data and instructions.  (^) Control Unit (CU) obtains and executes instructions.  (^) Arithmetic Logic Unit (ALU) does calculations.  (^) Accumulator is internal ALU storage for some data.  (^) Input is process of getting data into machine.  (^) Output is process of obtaining data from machine.

 (^) Most modern computers are Von Neumann machines!

Parts of a Modern Computer 2/

 (^) Central Processing Unit (CPU) : microchip that performs core computation. It usually contains the ALU and CU.  (^) Memory ( primary storage ): microchips that store data which can be accessed while computer is switched on.  (^) Random Access Memory (RAM) is volatile and modifiable.  (^) Read-Only Memory (ROM) cannot be changed.  (^) Hard drive , Floppy drive ( secondary storage ): store data on magnetic discs permanently i.e., the data is not lost when the computer is switched off.  (^) Input/Output devices : transfers data from operator to machine and vice versa.

 (^) Operating System : software system that manages resources on computer and executes application programs, e.g., Windows XP, Ubuntu Linux.

The IBM PC and compatibles ...

 Original IBM PC (1981), 8088, 4.77MHz

 XT (1983), 8086, 10MHz

 AT (1984), 80286, 20MHz

 80386 (1986), 33MHz

 80486 (1989), 66MHz

 Pentium I (93), 133MHz

 (^) II (97), 400MHz  (^) III (99) 1GHz  (^) IV (2000) 3GHz

 Intel Core 2 (2006), 2GHz

Programming Languages

Programming Languages Classes

 (^) The language directly understood by a computer is called machine language.  (^) E.g., B4 4C CD 21 terminates a program on a PC  (^) Assembly language is a low-level language with mnemonics (codes) used for each instruction to make programming easier for humans.  (^) E.g., MOV AH,4Ch INT 21h  (^) Low level languages are languages geared towards machines (computers).  (^) High-level languages are languages that are easier for humans to use.  (^) E.g., Java, C++, Pascal

Programming Languages Types 1/

 Imperative Languages

 (^) Programs state explicitly how problem is to be solved.  (^) Programs are broken down into named modules of sequential code.  (^) e.g., FORTRAN, COBOL

 Object-Oriented Languages

 (^) Special case of imperative languages.  (^) Real world is modeled as data+actions that can be performed on data.  (^) e.g., Java, Smalltalk

Programming Languages Types 2/

 Declarative Languages

 (^) Programs state what is to be solved – engine seeks out solution!  (^) Programs are stated as rules.  (^) e.g., Prolog, XSL

 Functional Languages

 (^) Programs state how problem is solved by applying and composing functions.  (^) Programs are stated as functions.  (^) e.g., LISP, Mathematica

Other Types of Software

 Systems Software

 (^) Operating System (Windows XP, Ubuntu Linux, etc.)  (^) Development Tools (Java compiler, Jgrasp, etc.)

 Applications Software

 (^) Office applications (OpenOffice, MSOffice, etc.)  (^) Utilities (Zip, Notepad, etc.)  (^) Internet applications (Firefox, IE, etc.)  (^) Games  (^) ...