This document provides information about database concepts and accessibility options in computers. It defines key database terms like table, row, field, data types and languages. It also explains database structures like flat file and relational databases. For accessibility, it outlines options to configure keyboard, sound, display and mouse settings to assist users with disabilities. These include features like sticky keys, toggle keys, high contrast and mouse keys.

1. Information Technology
Name :- Aayush Garg
Class :- 10 B
Roll No. :- 18
Submitted to :- Mrs. Arti Gupta Mam

2. Introduction
 A database prefer to collection of related data and database system.
 A database contain information about one particular enterprises.
 Intension of a database is that same collection of data should serve many
application as possible. Such as database would permit not only retrieval data but
also continuous modification of data.
 In a typical file processing system , permanent records are stored in various files . A
number of different application programs are written to extracts records from and
add records to the appropriate files.
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3. Database Working
The database system do not
maintain Separate copies of the
same data. All the data kept at
one place and all the application
that required data refer to the
centrally maintained Database. If
any change is to be made to
data, It will be made the same
change information will be
available at all the application
referring to it.
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4. Advantages Of Database
 Database reduce the data redundancy to a large extent. Data redundancy means
duplication of data.
 Database can control data inconsistency to a large extent. This is really a corollary
of the previous point.
 Database facilitate sharing of data. Sharing of data means that individual pieces of
database may be shared among several different users.
 Database enforce standards. The DBMS can ensure that all the data follow the
applicable standards.
 Data base can ensure data security.
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5. Data can be organized into two types:-
 Flat File: Data is stored in a single table. Usually suitable for less
 amount of data.
 Relational: Data is stored in multiple tables and the tables are
 linked using a common field. Relational is suitable for medium to
 large amount of data.
 Database Servers – Database servers are dedicated computers that
 hold the actual databases and run only the DBMS and related
 software. Databases on the database servers are accessed through
 command line or graphic user interface tools referred to as
 Frontends; database servers are referred to as Back-ends.
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6. RDBMS
 A relational database management system (RDBMS) is a
 database management system that is based on the relational
 model. In the relational model of a database, all data is
 represented in terms of tuples (rows), grouped into relations
 (tables). A database organized in terms the relational model is a
 relational database.
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7. DATABASE CONCEPT
 Database contains objects that are used for
 storing and managing information.
 1. Item : - Item is about which information is stored in the
 database.
 2. Field:- Each question that we ask about our item is a Field.
 3. Record:- Record is a set of information (made up of fields)
 stored in your database about one of the items.
 4. Value:- Value is the actual text or numerical amount or date
 that you put in while adding information to your database.
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8. TABLE
 A table is a set of data elements that is organized
 using a model of vertical columns and horizontal rows. Each row
 is identified by a unique key index or the key field.
 Column And Field
 A column is a set of data values of a
 particular simple type, one for each row of the table. For eg.
 Emp_Code , Emp_Name , Emp_Address etc.
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9. ROW OR RECORDS AND TUPLE
 A row represents a single,
 data items in a table. Each row in a table represents a set of
 related data, and every row in the table has the same structure.
 DATA TYPES :- Datatypes are used to identify the type of data
 we are going to store in the database.
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10. Categories of data types:-
 Data types can be broadly classified
 into five categories:-
 1. Numeric Types
 2. Alphanumeric Types
 3. Binary Types
 4. Date Time
 5. Other variable Types
 NUMERIC TYPES:- They are used for describing numeric values
 like mobile number, age, etc.
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11. The different types of numeric data types
available are-
 1. Boolean (Yes / No) 6. Numeric
 2. TinyInt (Tiny Integer) 7. Decimal
 3. SmallInt (Small Integer) 8. Real
 4. Integer 9. Float
 5. BigInt (Big Integer) 10. Double
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12. ALPHANUMERIC TYPES
 The list of different datatypes available in alphanumeric types
 are
 1. LongVarChar (Memo) (Long Text)
 2. Char (Text-fix) (Small Text)
 3. VarChar (Text) (Text of specified Length)
 4. VarChar_IgnoreCase (Text) (Comparisions are not case
 sensitive)
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13. BINARY TYPES
 Binary types are used for storing data in binary formats. It can be
 used for storing photos, music files or (in general file of any
 format) etc.
 The list of different datatypes available in Binary types are :-
 1. LongVarBinary (Image)
 2. Binary (Binary (fix)
 3. VarBinary (Binary)
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14. DATE TIME
 Date time data types are used for describing date and time values
 for the field used in the table of a database. It can be used for
 storing information such as date of birth, date of admission etc.
 The list of different data types available in Date Time type are :-
 1. Date (Stores month, day and year information)
 2. Time (Store hour , minute and second information)
 3. Timestamp (Stores date and time information
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15.  PRIMARY KEY:- A primary key is a unique value that identifies a
 row in a table. These keys are also indexed in the database,
 making it faster for the database to search a record.
 FOREIGN KEY:- The foreign key identifies a column or set of
 columns in one (referencing) table that refers to a column or set of
 columns in another (referenced) table.
 Note:- The “one” side of a relation is always the parent, and
 provides the PK(Primary Key) Attributes to be copied. The “many”
 side of a relation is always the child, into which the FK(Foreign
 Key) attributes are copied.
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16. THERE ARE TWO TYPES OF LANGUAGES
 1. DDL (Data Definition Language)
 2. DML (Data Manipulation Language)
 DATA DEFINITION / DESCRIPTION LANGUAGE:- It is a
 standard for commands that define the different structures in a
 database. DDL statements create,modify and remove database
 objects such as tables, indexes and users.
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17. Common DDL Statements are
 1. Create :- Used to create database objects.
 2. Alter :- Used to modify database objects.
 3. Drop :- Used to delete database objects.
 DATA MANIPULATION LANGUAGE:- It is a standard for
 commands that enables users to access and manipulate data in a
 database.
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18. Common DML Statements are:-
 1. SELECT :- Used for retrieval of information from the database.
 2. INSERT :- Used for insertion of new information into the
 database.
 3. DELETE :- Used for deletion of information in the database.
 4. UPDATE :- Used for modification of information in the database.
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19. Types of DML
 1.Procedural:- The user specifies what data is needed and how to
 get it.
 2. Non Procedural :- The user only specifies what data is needed.
 Note:- A popular data manipulation language is SQL (Structured
 Query Language.)
 In this article on SQL Commands, I am going to consider the
 below database as an example, to show you how to write
 commands.
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20. WORKING WITH ACCESSIBILITY OPTIONS
 Computer Accessibility refers to the user friendliness of a computer
 system for all, regardless of their disability., it enables a person with
 a disability or impairment to use a computer. It is known as
 Assistive Technology.
 LAUNCHING ACCESSIBILITY OPTIONS
 • To launch accessibility options in WindowsXP, Click Start >
 Control Panel > Accessibility Options.
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21. KEYBOARD TAB
 Sticky Keys
 StickyKeys is an accessibility feature to help computer users with
 physical disabilities, but it is also used by others as a means to
 reduce repetitive strain.
 FilterKeys
 FilterKeys is a feature of Microsoft Windows. It is an accessibility
 function that tells the keyboard to ignore brief or repeated
 keystrokes, making typing easier for people with hand tremors.
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22.  ToggleKeys
 ToggleKeys is also a feature of Microsoft Windows. It is an
 accessibility function which is designed for people who have vision
 impairment or cognitive disabilities. When ToggleKeys is turned on,
 computer emits sound cues when the locking keys (Caps Lock, Num
 Lock, or Scroll Lock) are pressed. A high sound is emitted when the
 keys are switched on and a low sound is emitted when they are
 switched off.
 Sound Tab
 Select the Sound Tab. A window with options to configure
 accessibility options for sound is displayed
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23.  SoundSentry
 SoundSentry is designed to help users with auditory impairments.
 SoundSentry generates visual warnings, such as a blinking title bar
 or a flashing border, whenever the computer generates a sound.
 ShowSounds
 ShowSounds instructs applications that convey information by sound,
 to also provide information visually, through text captions or
 informative icons.
 Display Tab
 Select the Display Tab. A window with options to configure
 accessibility options for display is displayed.
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24.  High Contrast
 High Contrast is an accessibility feature to assist people with vision
 impairment. You can change the size and color of fonts and the
 background for ease of viewing.
 Cursor Options
 Cursor Options is also an accessibility feature that assists people
 with vision impairment by changing the blink rate and width of the
 cursor.
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25. MOUSE TAB
 MouseKeys
 MouseKeys is an accessibility feature that assists people who have
 difficulty using a mouse. This option uses the keyboard (especially
 numeric keypad) as a pointing device instead of a mouse.
 General Tab
 This tab enables you to configure accessibility options for all users.
 Select the General Tab, a window to configure additional
 accessibility options will be displayed
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26. NETWORKING FUNDAMENTALS
 A computer network is a collection of computers and other hardware
 components interconnected by communication channels (cables or
 satellites) that allow sharing of resources and information.
 PEER-TO-PEER (P2P) ARCHITECTURE:
 Networks in which all computers have an equal status are called
 peer to peer networks. Generally in such a network each terminal
 has an equally competent CPU.
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27. CLIENT-SERVER ARCHITECTURE:
 Networks in which certain computers have special dedicated tasks,
 providing services to other computers (in the network) are called
 client server networks. The computer(s) which provide services are
 called servers and the ones that use these services are called
 clients.
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28. TYPES OF NETWORKS
 There are two major types of network Local Area Network (LAN)
 and Wide Area Network (WAN).
 LOCAL AREA NETWORK
 A local area network (LAN) is one which connects computers and
 devices in a limited geographical area such as home, school,
 computer laboratory, office building, or closely positioned group of
 buildings.
 Usually local area networks offer very high speeds and are used for
 connecting computers and peripherals such as printers, scanners,
 etc.
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29.  WIDE AREA NETWORK
 A wide area network (WAN) is one which covers a broad area (i.e.,
 any network that links across metropolitan, regional, or national
 boundaries). The Internet is the most popular WAN, and is used by
 businesses, governments, non-profit organizations, individual
 consumers, artists, entertainers, and many others.
 INTERNET
 The Internet is a global system of interconnected computer networks
 that use the standard Internet protocol suite to serve billions of
 users worldwide. It is a network of networks that consists of millions
 of private, public, academic, business, and government networks.
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30. Some of the advantages associated with
networking are
 •Data Sharing: One of the most important uses of networking is to
 allow the sharing of data.
 •Files transfer : Users can send text files, spread sheets,
 documents, presentations, audio files, video files, etc. to other users.
 •Hardware Sharing: Hardware components such as printers,
 scanners, etc. can also be shared.
 •Internet Access Sharing: You can purchase a single Internet
 connection and share it among other computers in a network
 instead of purchasing multiple Internet connection for each computer
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31.  GETTING ACCESS TO THE INTERNET
 To use the Internet, you need an Internet connection. Internet
 connections are provided by Internet Service Providers such as
 Bharat Sanchar Nigam Limited (BSNL), Airtel,Jio, Vodafone,
 INTERNET SERVICE PROVIDER
An Internet service provider (ISP) is an organization which provides
 you with access to the Internet via a dial-up (using modem) or
 direct (hard wired) or wireless connection.
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32. TYPES OF COMMON INTERNET CONNECTIVITY
 Types of Internet Connectivity can be broadly categorized into
 Wired Technology and Wireless Technology.
 Wired Technology
 1) Dial-up:- It uses the facilities of the Public Switched
 Telephone Network (PSTN) to establish a internet connection
 via telephone lines using a device called MODEM. Users dial
 a number and get access to internet. Dial-up connections are
 extremely slow.
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33.  2) DSL:- DSL is Digital Subscriber Line provides internet
 connectivity by transmitting digital data over wires of a local
 telephone network. It enables the use of Telephone and Data
 Transmission on a single telephone line. For using DSL
 Connection, we need a DSL modem and a subscription.
 3) Cable Internet Access:- It is a form of broadband Internet
 access that uses the cable TV infrastructure. It is provided
 through existing cable TV networks and it is similar to DSL.
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34. DATA TRANSFER ON THE INTERNET
 The data is broken up into bits of same sized pieces called
 packets.
 A header is added to each packet explaining where the data has
 come from, where it should end up and where it fits in with the
 rest of the packets.
 Each packet is sent from computer to computer until it finds its
 destination. All packets may not take the same route.
 At the destination, the packets are examined. If any packets are
 missing or damaged, a message is sent asking for them to be
 resent. This continues until all packets have been received intact.
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35. CHATTING WITH A CONTACT – GOOGLE TALK
 Whenever your friend in the contact list is online you can see the
 person along with a green dot.
You can start sending text chat message instantly by double-
 clicking on a contact.
 •Messages should be short and to the point.
 • Always introduce yourself by name if your screen name doesn’t
 reflect it.
Always ask if the other person has time to chat first - regardless
 of how important you think what you have to say is, it’s not going
 to be well received if the recipient is busy.
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36. USING OFFLINE BLOG EDITORS
 If you do not have an active internet connection, you can create
 blogs using a blog application and publish the blog whenever
 internet connectivity is available.
 There are several free offline blog editors available that can be
 downloaded and installed on the local computer such as:
 • Qumana
Windows Live Writer
Blogdesk
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37. ONLINE TRANSACTIONS
 The transactions over the internet are called Online Transactions
 Like purchasing of goods, selling of goods, booking a ticket,
 payment of fees etc. all comes under the category of Online
 transactions
 Examples
 1) For Buying Goods :- amazon, jabong, myntra, flipkart , ebay
 etc.
 2) For Booking of Tickets :- IRCTC , Redbus etc.
 3) For Payment of School fees
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38. INTERNET SECURITY
 Objectives of Internet Security
 The main objective of internet security is to establish rules and
 measures to use against attacks over the internet.
 Online Threats
 The threats / vulnerabilities that uses World Wide Web (Internet)
 to facilitate crimes are called Online Threats.
 Like:-
 1) Phishing :- The act of acquiring personal / private and
 sensitive data from personal computers for use in fraudulent
 activities. For eg. Mails from unknown persons that ask for
 your credit / debit card details.
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39.  Email spoofing :- It is the creation of email messages with a
 forged sender address. For eg. Sending an email with a
 forged email address which appears to be original. These
 mails are infected mails which contain worms.
 Chat Spoofing:- Spoofing means hoax, trick, or deceive which
 contains false information. Hiding / Faking the identity of
 another person over the internet is called chat spoofing
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40. Maintain workplace safety
 Basic safety rules to follow at workplace – Fire safety, Falls and
 slips, Electrical safety, Use of first aid.
 Basic Fire safety rules in an organization are :
 - Fire escape plans must be installed at proper levels
 - Conduct regular drills
 - Maintenance of safety equipment must be taken care of
 Regularly
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41. Prevent Accidents and Emergencies
 Accident: an accident is an unplanned event that may happen all of
 a sudden and may lead to unwanted or unprecedented
 results/outcomes.
 Handling accidents:
 - Safety measures must be placed to prevent workplace
 accidents
 - Immediately call the medical team for any injury
 - Stay alert
 - Pay attention to and follow emergency drills
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