Information Technology

Friday, August 17, 2018

Evolution of Computers

6:36 AM mayuravaani

First Generation (1940-1956)

Image result for generation of computer png

Major Hardware Technology: Vacuum Tubes, Punch Cards
Used Machine language
High heat generation
Slow processing
Large in size
Not portable
Consumes a lot of electricity
Expensive
System Invented: ENIAC, UNIVAC, IBM704, EDVAC, EDSAC

Second Generation (1956-1963)

Major Hardware Technology: Transistors, Tape
Use of Assembly language
Smaller in siz
Less heat generation
Less power consumption

Tuesday, August 14, 2018

Shutdown, Sleep, Hibernate

5:44 PM mayuravaani

Shutdown

when you finish your work with pc or no need or infrequently usage then you can shutdown the pc.

You should save your current works before shutting down

if not, you will permanently loss your current work.

Sleep

sleep is a power saving state that allows a computer to quickly resume full-power operation when you want to start working again.
In sleep mode, your current work is saved in the RAM.

It will consume less power and often disable hardware and suspend software to assist in reducing power consumption.
It the power is cut while sleep mode, most probably it will lost your works where you left.
In hybrid sleep mode,with RAM it always save the current work to the hard disk for safe keeping in the event of power cut.

Hibernate

Hibernate mode is almost the same thing as fully shutting down the PC, but it saves your place to resume the next time you turn it on.
Instead of saving to your RAM like sleep mode, it saves straight to your hard disk so that there's no chance of losing anything if power is cut.
It takes bit longer than the sleep mode but it depends on the hard disk and RAM speed.

difference

Friday, August 10, 2018

HTML5- Content models

3:02 PM mayuravaani

Meta data
Content that sets up the presentation or behavior of the rest of the content. These elements are found in the head of the document.
Elements:
<base>, <link>, <meta>, <noscript>, <script>, <style>, <title>

Embedded
Content that imports other resources into the document.
Elements:
<audio>, <video>, <canvas>, <iframe>, <img>, <math>, <object>, <svg>

Interactive Content specifically intended for user interaction.
Elements:
<a>, <audio>, <video>, <button>, <details>, <embed>, <iframe>, <img>, <input>, <label>, <object>, <select>, <textarea>

Heading
Defines a section header.
Elements:
<h1>, <h2>, <h3>, <h4>, <h5>, <h6>, <hgroup>

Phrasing
This model has a number of inline level elements in common with HTML4.
Elements:
<img>, <span>, <strong>, <label>, <br />, <small>, <sub>, and more.

Flow
Contains the majority of HTML5 elements that would be included in the normal flow of the document.

Sectioning
Defines the scope of headings, content, navigation, and footers.
Elements:
<article>, <aside>, <nav>, <section>

3 Comments

Tuesday, July 31, 2018

Digital image editing, Digital image processing, Computer graphics

6:30 AM mayuravaani

Digital image editing is the manipulation of digital images using existing software applications such as Adobe Photoshop or Coral paint.

Digital image processing is the conception, design, development and enhancement of digital imaging programs.

Computer graphics concentrates on the synthesis of digital images from geometrical descriptions such as three dimensional object models.

difference

Monday, July 30, 2018

VirtualBox - Intro

7:29 PM mayuravaani

VirtualBox is a software virtualization package that installs on an operating system as an application.

It allows additional operating system to be installed on it as a guest operating system and run in virtual environment.

VirtualBox may be installed on a number of host operating systems, including: Linux, macOS, Windows, Solaris, and OpenSolaris.

Remote Sensing

3:59 PM mayuravaani

Remote means far away. Remote sensing means sensing things from a distance. We use three as remote sensors of our five senses. Sense of sight (watching cricket from the stands), Sense of smell (smell freshly baked food) and sense of hearing (hear a telephone call) are remote sensors.

Remote sensing is used in numerous fields. There are two types of remote sensing. Passive remote technology is used to record an object’s natural radiation. For example, an infrared camera on a tripod that records heat coming from a rock formation or an airplane flying over a rain forest that registers the sunlight reflected from the forest as canopy.

“” Science and art of identifying, observing and measuring an object without coming into direct contact “
-Ms. Evelyn Pruitt of the U.S office Naval Research

Active remote technology takes place when a device sends out a signal in order to gather information about an object. For example, Ships that send sonar waves to scan the ocean floor uses active remote sensing.

Google Assistant - AI

3:29 PM mayuravaani

AI is helping people everywhere solve problems big and small

Ready to help, Just say “Hey Google”.

phone

Talk or type to the assistant
Manage Tasks- Send texts, set reminders, instantly lookup emails, set alarms, everyday weather forecast, play latest news
Get help on the head phone
Have funs –play game, tell jokes, poems, quotes, control music on Google play
Navigate the routs
Use the phone to control your smart home devices and adjust the temperature, lighting and more, even you are not at home

Smart watch and warbles

Track your run, return a call
Add things to the shopping list
Check the time in any city, ask to get translations and updates while you are on the go

Monday, July 9, 2018

Hey google! - google assistant

7:40 PM mayuravaani

Cloud Computing Intro

7:38 PM mayuravaani

Cloud computing refers to storing and accessing data and the programs over the internet.

Cloud computing models:

SaaS
PaaS
IaaS

SaaS (Software as a Service)

In this service the service provider provides software/ application to its clients.
The clients can access these software in any device which is connected to the internet using network applications such as web browser.

Eg: Google Applications (gmail, googledrive and googledocs etc), dropbox

PaaS (Platform as a Service)

In this service the cloud provider gives the ability to the customer to deploy applications created by customer by programming languages, tools etc which are provided by cloud provider.
It typically includes operating system, database, programming language execution environment, web server etc.

Eg: Google app Engine, Apache Stratos

IaaS (Infrastructure as a Service)

In this service cloud provider provide the customer with virtual machines and the resources as the service they abstract the user from a physical machine, location, data partition etc.

Eg: aws (Amazon Web Service)

Sunday, July 8, 2018

AI- Robot Interview

9:24 PM mayuravaani

Friday, July 6, 2018

Virtual reality painting

8:20 PM mayuravaani

Wednesday, July 4, 2018

HTML- 2016/2017 G.C.E A/L Past papers Question & Answer Tamil Medium

7:43 PM mayuravaani

Click here to view Questions

Click here to view Answers

Thursday, June 28, 2018

www - Tim Berners-Lee

12:54 PM mayuravaani

Sir Tim Berners-Lee created a paradigm shift by inventing world wide web, the URL naming scheme, HTTP protocol, and the HTML markup language.
At that time, he was working at CERN the Europian Organization Nuclear Research center which is in Geneva.
He had his undergraduate degree in physics from The Queen's College, Oxford, but had no formal training as a computer scientist, although he had bulit his own computer and written software, and it was that combination of skills CERN needed.
There were perhaps 10,000 people working for CERN at the time, but only 3,000 actual campus; others were coming and going there and other institutions.
Berners-Lee thought it would be useful to have an online collabarative space where people could share ideas, and where people who came along later could follow the decision-making process by clicking through the links.
However, just bringing co-workers together did not seem like enough.
By 1989, the internet was beginning to become generally connected.
After that Tim Berners-Lee beleived the web should allow anybody anywhere to create information and link to it.
He expose his thought to his Boss Mike Sandall. His boss said him to do that as a side project.
Because he couldn't justify that it the project has a direct relation to CERN's goals. Instead, he decided it could be a good way of testing the potential of the NeXT machine which belongs to Apple. designed by Steve Jobs.

List of web browsers and search engines

11:37 AM mayuravaani

Web browser

Netscape Navigator
Mosaic
Internet Explorer
Google Chrome
Mozilla Firefox
Safari
Opera
Microsoft Edge

Search engine

Google
Bing
Yahoo
ask.com
Baidu

Sunday, June 24, 2018

Version Names of Operating Systems

8:58 AM mayuravaani

Windows

Windows 95
Windows 2000
Windows XP
Windows Vista
Windows 8
Windows 7
Windows 10
Windows server 2003
Windows server 2008
Windows server 2012
Windows Phone 7
Windows Phone 8
Windows CE (Satellite Navigation System and some Mobiles)

Apple mac OS

Mac OS X Public Beta
Mac OS X 10.0 Cheetah
Mac OS X 10.1 Puma
Mac OS X 10.2 Jaguar
Mac OS X 10.3 Panther
Mac OS X 10.4 Tiger
Mac OS X 10.5 Leopard
Mac OS X 10.6 Snow Leopard
Mac OS X 10.7 Lion
Mac OS X 10.8 Mountain Lion
Mac OS X 10.9 Mavericks
Mac OS X 10.10 Yosemite
Mac OS X 10.11 EI Capitan
Mac OS X 10.12 Sierra
Mac OS X 10.13 High Sierra
Mac OS X 10.14 Mojave

Apple iOS

iPhone OS 1
iOS 2
iOS 3
iOS 4
iOS 5
iOS 6
iOS 7
iOS 8
iOS 9
iOS 10
iOS 11
iOS 12

Android

Android 1.6 Donut
Android 2.1 Eclair
Android 2.2 Froyo
Android 2.3 Gingerbread
Android 3.0 Honeycomb
Android 4.0 Ice Cream Sandwich
Android 4.1 Jelly Bean
Android 4.4 KitKat
Android 5.0 Lollypop
Android 6.0 Marshmallow
Android 7.0 Nougat
Android 8.1 Oreo

Linux

Red Hat Linux
Cent OS
Fedora
Mandrake Linux
openSUSE

Wednesday, June 6, 2018

Computer and internet crimes

5:12 PM mayuravaani

Why computer incidents are so prevalent

In today's computing environment of increasing complexity, higher user expectations, expanding and changing systems, and changing systems, and growing reliance on software with known vulnerabilities, it is no wonder that the number, variety, and impact of security incidents are increasing dramatically. Computer security incidents occur around the world with personal computer users in developing countries being exposed to the greatest risk of their computers being infected by malware.

Increasing complexity increasing vulnerability
virtualization
higher computer user expectation
Expanding and changing systems introducing new risks

Types of Exploits

There are numerous types of attacks, with new varieties being invented all the time.

Viruses

Computer virus has become an umbrella term for many types of malicious code. Technically, a virus is a piece of programming code, usually disguised as something else, that causes a computer to behave an an unexpected and usually undesirable manner. Often a virus is attached to a file, so that when the infected file is opened, the virus executes.Other viruses sit in a computer's memory and infect files as the computer opens, modifies, or creates them. Most viruses deliver a "play load" or malicious software that causes the computer to perform in an unexpected way.For example, the virus may be programmed to display a certain message on the computer's display screen ,delete, delete or modify a certain document or reformat the hard drive.

A true virus does not spread itself from computer to computer. A virus is spread to other machines when a computer user opens an infected email attachment, downloads an infected program, or visits infected program, or visits infected web sites.

Macro viruses have become a common and easily created form of virus.Attackers use an application macro language to create programs that infect documents and templates. After an infected document is opened, the virus is executed and infects the user's application templates. Macros can inset unwanted words , numbers, or phrases into document or alter command functions.

Worms

It is a harmful program that resides in the active memory of the computer and duplicates itself. Worms differ from virus in that they can propagate without human intervention, often sending copies of themselves to other computers by email.
The negative impact of worms

Lost data and programs
Lost productivity due to workers being unable to use their computers
Additional lost productivity as workers attempt to recover data and programs

Challenges of Information Technology

4:42 PM mayuravaani

Friday, February 23, 2018

File Extensions stands for...

11:37 PM mayuravaani

jpeg - joint photographic experts group
png - portable network grapics
gif - graphic interchange format
tiff - tagged image file format
svg - scalar vector graphics
pdf - portable document format
html - hypertext markup language
php - hypertext preprocessor
sql - structured query language
wmv - windows media video