MPPSC 2019-2020 COMPUTER
What is Computer ?
Ans- A Computer is an electronic device which can accept data in the prescribed form. ie. in a Specific sequence.
DATA ---- PROCESS---- INFORMATION
Five Generations of Computer -
1. 1940-52----- Electronic valve vacuum tube---- UNIVAC, EDSAC
2. 1952-64----- Transistor --------------------------- IBM-700, ATLAS
3. 1964-71----- Integrated Circuit ----------------- IBM-360
4. 1971--------- Largely Integrated Circuit------- APPLE, DCM
5. Present ----- Optical fibre, Artificial fibre---- ----------------
Fastest Supercomputer -
SUMMIT --------- 2018 ------ USA
SuperComputer in India -
SuperComputer PARAM 8000 (Made by C-DAC) was launched on july 1 -1991 is Considered India's First Supercomputer.
( C-DAC - Centre for Development of Advanced Computing )
2. Virgo -IIT Madras
3. EKA - Computer Research Laboratories.
4. SAGA-220- ISRO
5. Param Yuva 2 - C-DAC
6. Prithvi - India Institute of Tropical Meteorology , PUNE.
Types of Computer-
1. Micro Computer - These Computer are used by individual , thus also called PC.
2. Mini Computer -This is 5 to 50 times more powerful than that of a micro Computer.
3. Mainframe Computer- These are large sized computers . by time sharing and multitasking techniques many people rather than 100 people can work at a time on different terminals of this computer.
4. SuperComputer - These are very powerful computers and have more storage capacity. they are able to process most complex jobs with a very high speed.
5. Quantum Computers - Probably Quantum Computers will be more advanced than that of Human brain. In Quantum Computers Q-Bit will be used in Lieu of Binary Bits.
CPU- Central Processing Unit
CU- Central Unit.
ALU- Arithmetic Logical Unit.
Types Of Memory-
1. Cache Memory
2. Primary Memory
3. Secondary Memory
Cache Memory
The word Cache is pronounced as Cash.
The Cache memory is placed between the CPU and Main Memory ie. It acts as a buffer between the CPU and the Main Memory.
Note - Primary Memory is only type of memory which is directly accessed by the CPU.
RAM ( Random Access Memory )
RAM is a Volatile Memory with in the computers that is typically used to store data temporarily , so that it can be accessed by the processor.
ROM ( Read Only Memory )
Non Volatile Memory ie. the information stored in it is not lost even if the power supply cut off. It is used for Permanent Storage of Information.
Floppy Disk - A floppy is made of plastic with magnetic coating on it.
Note - A language acceptable to a computer system is called Programming Language or Computer language.
WWW ( World Wide Web ) -The www is a collection of linked documents or pages , stored on millions of computers and distributed a across the world.
Web Page -The Hypertext documents in the internet are known as web pages.
A web page is written in a special language called HTML.
HTML - Hypertext markup language.
URL -( Uniform Resources Locator ) -
Each Web Page has unique address called a URL ( Or Web Address) which identifies its location on the internet.
The format of URL Contains four parts - protocol name of the web server ( or domain name ), path and file name.
ex- http://www
http is a protocol
host name - www.gkgsboss.blogspot.com
file name - index.html
Domain type-
com - Commercial
gov - Governmental
net - network resource
org - Non profit Organisation.
mil - military
edu - colleges and universities
info - informational organisation
Domain Name for Countries-
uk- united kingdom
in - india
us- united states
de - germany
etc....
Web Browser -
It is a special software that enables users to read.
ex -
1. Internet Explorer
2. Mozilla Firefox
3. NetScape Navigator
4. Google Chrome
5. Apple Safari
6. Microsoft Edge.
7. Vivaldi
8. Camino
9. Surf
10. Palemoon
11. Sea Monkey
12. Maxthon
13. Epiphany
14. Phoenix
15. Cyberdog
16. Amaya
17. Voyager
18. Mosaic
19. Cello
20. Agora
21. Grail.
22. Chromimum
23. Avant Browser
24. Kon Queror
25. Lynx
26. Torch
27. Rockmelt
28. K- Meleon
29. Midori
30. Luna Scape
31. Icab
32. Epic
33. Comodo ice dragon
34. Dillo
35. Arora
36. Galeon
37. Aol Explorer
Difference
Between Malware, Trojan, Virus, and Worm
Malware
Any software
intentionally designed to cause damage to a computer, server or computer
network. Malware does the damage after it is implanted or introduced in some
way into a target’s computer and can take the form of executable
code, scripts, active content, and other software.
Malware can be classified based on how they get executed, how
they spread, and/or what they do. Some of them are –
Viruses
Worms
Trojan horses
Spyware
Hoax
Computer
Viruses –
It is a type of malicious software
program ( Malware) that, when executed , replicates itself by modifying other
computer programs and inserting its own code.
VIRUS- Vital Information Resources under Siege.
List of most destructive computer virus
Worms
Worms disseminates
from computer to computer, but unlike a virus, it has the capability to travel
without any human action. worms are malicious programs
that copy themselves from system to system, rather than infiltrating legitimate
files. The example would be for a worm to send a
copy of itself to everyone listed in your e-mail address book.
the worm replicates and sends itself
Trojan horse
A
type of malicious software program , Trojans do not replicate or reproduce through infection.
Trojans may allow an
attacker to access users' personal information such as banking information,
passwords, or personal identity. It can infect other devices connected to the network. Ransomware attacks are often carried out using a Trojan.
Spyware
Malware that collects information about the usage of the
infected computer and communicates it back to the attacker. "Spyware"
is mostly classified into four types: adware, system monitors,
tracking cookies, and trojans, Spyware can
collect almost any type of data, including personal information like internet surfing habits, user logins, and bank or credit account
information.
Spyware can also interfere with a user's control of a computer by
installing additional software or redirecting web browsers. Some spyware can change computer settings, which can result
in slow Internet connection speeds, unauthorized changes in browser settings,
or changes to software settings.
World Wide Web
The World Wide Web,
also known as the WWW and the Web, is an information space where
documents and other web resources are
identified by Uniform Resource Locators (URLs),
interlinked by hypertext links,
and accessible via the Internet.
Tim Berners-Lee invented the
World Wide Web in 1989. He wrote the first web browser in 1990 while employed at CERN near Geneva, Switzerland.
The terms Internet and World
Wide Web are often used without much distinction. However, the two are
not the same. The Internet is a global system of interconnected computer networks. In contrast, the World Wide Web is a global
collection of documents and other resources, linked by hyperlinks and URIs. Web resources are accessed using HTTP or HTTPS, which
are application-level Internet protocols that use the Internet's transport
protocols.
A web cache is a server computer located either on the public
Internet, or within an enterprise that stores recently accessed web pages to
improve response time for users when the same content is requested within a
certain time after the original request.
A Web server is
a program that uses HTTP(Hypertext Transfer Protocol) to serve the
files that form Web pages to users, in response to their
requests, which are forwarded by their computers'HTTP clients.
Dedicated computers and appliances may be referred to as Web servers as
well.
Spam refers to the use of
electronic messaging systems to send out unrequested or unwanted messages in
bulk.
The most common form of spam is email spam, but the
term also applies to any message sent electronically that is unsolicited and
bulk. This includes: instant message spam, search
engine spam, blog spam, Usenet newsgroup spam, wiki spam, classified ads spam,
Internet forum spam, social media spam, junk fax spam, and so on.
A video conference is a live, visual
connection between two or more people residing in separate locations for the
purpose of communication. At its simplest, video conferencing provides
transmission of static images and text between two locations. At its most
sophisticated, it provides transmission of full-motion video images and
high-quality audio between multiple locations.
Or
Video conferencing refers
to conducting a video conference or video teleconference in which two or more
sets of hardware and software interact while simultaneously transmitting and
receiving video and audio signals from two or more geographic locations. Video
conferencing may also involve sharing documents, various presentation
materials, whiteboards, flip charts and similar group presentation visual aids.
list of
video conferencing software
ClickMeeting
Livestorm
Flock
Zoho Meeting
Samepage
BigMarker
A suite
TeamViewer's
Cisco WebEx
ReadyTalk
Cybercrime is defined as a
crime in which a computer is the object of the crime (hacking, phishing,
spamming) or is used as a tool to commit an offense (child pornography, hate
crimes). Cybercriminals may use computer technology to access personal
information, business trade secrets or use the internet for exploitative or
malicious purposes. Criminals can also use computers for communication and
document or data storage. Criminals who perform these illegal activities are
often referred to as hackers.
Phishing is the fraudulent attempt to obtain
sensitive information such as usernames, passwords and credit card details by disguising as a trustworthy entity in an
electronic communication.
Phishing is a type of social engineering attack often used to
steal user data, including login credentials and credit card numbers. It occurs
when an attacker, masquerading as a trusted entity, dupes a victim into opening
an email, instant message, or text message.
Cyberstalking is a
criminal practice where an individual uses the Internet to systematically
harass or threaten someone. This crime can be perpetrated through email, social
media, chat rooms, instant messaging clients and any other online medium.
Cyberstalking can also occur in conjunction with the more traditional form of
stalking, where the offender harasses the victim offline. There is no unified
legal approach to cyberstalking, but many governments have moved toward making
these practices punishable by law.
Cyberstalking is sometimes referred to as
Internet stalking, e-stalking or online stalking.
A Denial-of-Service
(DoS) attack is an attack meant to shut down a machine or network,
making it inaccessible to its intended users. DoS attacks accomplish this by
flooding the target with traffic, or sending it information that triggers a
crash. In both instances, the DoS attack deprives legitimate users (i.e.
employees, members, or account holders) of the service or resource they
expected.
A hacker is an individual
who uses computer, networking or other skills to overcome a technical problem.
The term hacker may refer to anyone with technical skills, but it often refers
to a person who uses his or her abilities to gain unauthorized access to
systems or networks in order to commit crimes. A hacker may, for example, steal
information to hurt people via identity theft, damage or bring down systems and, often, hold
those systems hostage to collect ransom.
However, the term is more
commonly applied to an individual who uses this skill for illegal or unethical
purposes.
Types of hackers
A white hat hacker is a
computer security specialist who breaks into protected systems and networks to
test and asses their security. White hat
hackers use their skills to improve security by exposing vulnerabilities before
malicious hackers (known as
black hat hackers) can detect and
exploit them. Although the methods
used are similar, if not identical, to those employed by malicious hackers,
white hat hackers have permission to employ them against the organization that
has hired them.
White hat hackers are
usually seen as hackers who use their skills to benefit society. They may be
reformed black hat hackers or they may simply be well-versed in the methods and
techniques used by hackers.
Or
An
ethical hacker (also known as a white hat hacker) is the ultimate security
professional. Ethical hackers know how to find and exploit vulnerabilities and
weaknesses in various systems—just like a malicious hacker (or a black hat
hacker). In fact, they both use the same skills; however, an ethical hacker
uses those skills in a legitimate, lawful manner to try to find vulnerabilities
and fix them before the bad guys can get there and try to break in.
Black hat hackers intentionally gain
unauthorized access to networks and systems with malicious intent, whether to
steal data, spread malware or profit from ransomware, vandalize or otherwise
damage systems or for any other reason -- including gaining notoriety. Black hat hackers are
criminals by definition because they violate laws against accessing systems
without authorization, but they may also engage in other illegal activity,
including identity theft and distributed denial-of-service
attacks.
Gray hat hackers fall somewhere between white hat hackers and black
hat hackers. While their motives may be similar to those of white hat hackers, gray hats are more
likely than white hat hackers to access systems without authorization; at the same time,
they are more likely than black hat hackers to avoid doing unnecessary damage
to the systems they hack. Although they aren't typically -- or only -- motivated by money, gray
hat hackers may offer to fix vulnerabilities they have discovered through their
own, unauthorized, activities rather than using their knowledge to exploit
vulnerabilities for illegal profit.
A cracker is someone who
breaks into someone else's computer system, often on a network; bypasses
passwords or licenses in computer programs; or in other ways intentionally
breaches computer security. A cracker can be doing this for profit, maliciously,
for some altruistic purpose or cause, or because the challenge is there. Some
breaking-and-entering has been done ostensibly to point out weaknesses in a
site's security system.
The crackers are
also known as Black Hats. They gain access to the accounts of people
maliciously and they can misuse the secured information across networks.
Hacker vs. cracker
Within the hacker-cracker framework, hackers
are those who seek to identify flaws in security systems and work to improve
them, including security experts tasked with locating and identifying flaws in
systems and fixing those vulnerabilities. Crackers, on the other hand, are
intent on breaching computer
and network security to exploit those same flaws for their own gain.
Script kiddie
n programming and hacking
culture, a script kiddie, skiddie,[1] or skid is an unskilled individual who uses scripts or programs developed by others to attack
computer systems and networks and deface
websites. It is generally assumed
that most script kiddies are juveniles who lack the ability to write
sophisticated programs or exploits on their own and that their objective is to
try to impress their friends or gain credit in computer-enthusiast communities.
video
chatting & videoconferencing
While
video chatting is often used interchangeably with the term videoconferencing -- and there is
considerable overlap between the two -- in most cases videoconferencing refers
to multipoint (3 or more participants) audio and video interaction deployed in
a business setting, whereas video chatting most frequently refers to one-to-one
video calls made via software apps like Skype.
Video
conference refers to a
communication over a distance between three or more people where video and
audio is transmitted in near real-time.
Conduct of video call using telecom technology.
Ethernet
Ethernet is the
traditional technology for connecting wired local area networks (LANs), enabling devices to communicate with
each other via a protocol -- a set of rules or common network language.
LAN
A LAN (local
area network) is a group of computers and network devices connected together,
usually within the same building. By definition, the connections must be high
speed and relatively inexpensive (e.g., token ring orEthernet). Most
Indiana University Bloomington departments are on LANs.
A LAN connection is a
high-speed connection to a LAN. On the IUB campus, most connections are either
Ethernet (10 Mbps) or Fast Ethernet (100 Mbps), and a few locations have
Gigabit Ethernet (1000 Mbps) connections.
MAN
A MAN (metropolitan
area network) is a larger network that usually spans several buildings in the
same city or town. The IUB network is an example of a MAN.
WAN
A WAN (wide
area network), in comparison to a MAN, is not restricted to a geographical
location, although it might be confined within the bounds of a state or
country. A WAN connects several LANs, and may be limited to an enterprise (a
corporation or an organization) or accessible to the public. The technology is
high speed and relatively expensive. The Internet is an example of a
worldwide public WAN.
A modem modulates
outgoing digital signals from a computer or other digital device to analog signals for a conventional copper twisted pair telephone line and demodulates the incoming analog
signal and converts it to a digital signal for the digital device.
DSL
(Digital Subscriber Line)
DSL (Digital Subscriber
Line) is a technology for bringing high- bandwidth information to homes and small businesses over ordinary
copper telephone lines. xDSL refers to different variations of DSL, such as
ADSL, HDSL, and RADSL.
a) Bit - It is a starting Memory unit It is a value of smallest digital measurement. it has two possible values off or 0 and on or 1.
b) Nibble - it is equal to 4 bits.
c) Byte - it has 8 bits.
d) Kilobyte - A kilobyte is 1024 bytes.
e) Megabyte - it has 1024 kilobytes.
f) Gigabyte - it is equal to 1024 megabytes or 1048576 bytes.
g) Terabyte - it is equal to 1024 gigabytes or 1048576 megabytes.
h) Petabyte - it is equal to 1024 terabytes or 1048576 gigabytes.
i) Exabyte - it is equal to 1024 petabytes or 1048576 terabytes.
j) Zettabyte -it is equal to 1024 exabytes or 1048576 petabytes.
k) Yottabyte - it is equal to 1024 zettabytes or 1048576 exabytes.
Binary is a base 2 number system invented by Gottfried Leibniz that is made up of only two numbers: 0 and 1.
This number system is the
basis for all binary code, which is used to write data such as
the instructions that computer processors use, or the digital text you read
every day.
Fireball (software)
Fireball is a form of malware orchestrated by Rafotech, a Beijing-based digital
marketing agency, that has infected up to 250 million Windows and MacOS computers, according to Check Point software.
Once it infects a computer, Fireball
takes over the PC's browsers and
turns them into zombies, enabling the Fireball Browser Hijack malware to run any
code on the infected computer as well as hijacking and manipulating the web
traffic of the infected PC to help generate fraudulent ad revenue.
|
Country
|
% infected
|
Number of infections (in millions)
|
Hit Rate
|
|
India
|
10.1%
|
25.3
|
43%
|
|
Brazil
|
9.6%
|
24.1
|
38%
|
|
Mexico
|
6.4%
|
16.1
|
N/A
|
|
Indonesia
|
5.2%
|
13.1
|
60%
|
|
US
|
2.2%
|
5.5
|
10.7%
|
ALL COMPUTER RELATED FULL FORM
Internet Related
HTTP - Hypertext Transfer Protocol
HTML - Hypertext Markup Language
HTTPS - Hypertext Transfer Protocol
Over Secure Sockets Layer
PHP - Hypertext Preprocessor
SASS - Syntactically Awesome Style
Sheets
PERL - Practical Extraction and
Reporting Language
UI - User Interface
ASP - Active Server Pages
NET - Internet
WP - WordPress
WWW - World Wide Web
API - Application Programming
Interfaces
BIOS - Basic Input/Output System
DNS - Domain Name Service Or
Domain Name Server
DPI - Dots Per Inch
DVI - Digital Visual Interface
FAT - File Allocation Table
FPS - Frame Per Second
EMI - Electromagnetic Interference
GBps - Gigabytes per second or
Gigabits per second
GHz - Gigahertz
GUI - Graphical User Interface
Mbps - Mega Bytes Per second
MHz - Megahertz
MP3 - Moving Picture Experts
Group Layer 3 Audio
MPEG - Moving Picture Experts
Group
NTFS - New Technology File System
OMR - Optical Mark Recognition
SD - SECURE DIGITAL
PC - Personal Computer
OS - Operating System
VDU - Visible Display Unit
ZIP - Zigzag Inline Package
IT - Information Technology
ISO - International Standards
Organization
AMD - Advanced Micro Devices
CD - Compact Disc
CD-ROM - Compact Disc-Read-Only
Memory
CD-RW - Compact Disc-Rewritable
Computer - Commonly Operated Machine
Particularly Used In Technical And Educational Research.
CPU - Central Processing Unit
DVD - Digital Versatile Disc
DVD-ROM - Digital Video Disc-Random
Access Memory
DDR - Double Data-Rate
FDD - Floppy Disk Drive
HDD - Hard Disk Drive
HDMi -High Definition Media
Interface
LCD - Liquid Crystal Display
LED- Light Emitting Diode
USB - Universal Serial Bus
VGA - Video Graphics Array
VRAM - Video Random Access Memory
.sub -Subtitle File
.wav - Waveform PCM Audio
.mp3 - MPEG Audio Layer 3
.mp4 - MPEG Layer 4
.avi - Audio Video Interleave
.flv - Flash Video
.wmv - Windows Media Video
.mpeg - Moving Picture Experts
Group
.ppt - PowerPoint Presentation
.pdf - Portable Document Format
.gif - Graphics Interchange Format
.docx - Document (without Macros)
.docm - Document (with Macros)
IMDb - The Internet Movie Database
DELL - Digitle Electronic Link
Library
WIPRO- Western Indian Products
HP - Hewlett-Packard
LG - Life’s Good
INTEL - Integrated Electronics
YAHOO - Yet Another Hierarchical
Officious Oracle
IBM - International Business
Machines Corporation
