What is markup language?

A set of codes in a text file that instructs a computer how to format the file on a printer or video display or how to index and link its contents. Examples of markup languages are Hypertext Markup LanguageHTML and Extensible Markup Language XML, which are used in Web pages, and Standard Generalized Markup Language SGML, which is used for typesetting and desktop publishing purposes and in electronic
documents. Markup languages of this sort are designed to enable documents and other files to be platform-independent and highly portable between applications. See also HTML, SGML, XML.

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why need For a relational database?

A database or database management system that stores information in tables—rows and columns of data—and conducts searches by using data in specified columns of one table to find additional data in another table. In a relational database, the rows of a table represent records (collections of information about separate items) and the columns represent fields (particular attributes of a record). In conducting searches, a relational database matches information from a field in one table with information in a corresponding field of another table to produce a third table that combines requested data from both tables. 

For example, if one table contains the fields EMPLOYEE-ID, LAST-NAME, FIRST-NAME, and HIRE-DATE, and another contains the fields DEPT, EMPLOYEE-ID, and SALARY, a relational database can match the EMPLOYEE-ID fields in the two tables to find such information as the names of all employees earning a certain salary or the departments of all employees hired after a certain date. In other words, a relational database uses matching values in two tables to relate information in one to information in the other. Microcomputer database products typically are relational databases. Compare flat-file database, inverted-list database.

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Os registry?

A central hierarchical database in Windows 9x, Windows CE, Windows NT, and Windows 2000 used to store information necessary to configure the system for one or more users, applications, and hardware devices. The Registry contains information that Windows continually references during operation, such as profiles for each user, the applications installed on the computer and the types of documents each can create, property sheet settings for folders and application icons, what hardware exists on the system, and which ports are being used.

 The Registry replaces most of the text-based .ini files used in Windows 3. x and MS-DOS configuration files, such as AUTOEXEC.BAT and CONFIG.SYS. Although the Registry is common to the several Windows platforms, there are some differences among them. Also called: system registry. See also hierarchical database, .ini, input/output port, property sheet, Registry Editor.

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Whai is macro?

In applications, a set of keystrokes and instructions recorded and saved under a short key code or macro name. When the key code is typed or the macro name is used, the program carries out the instructions of the macro. Users can create a macro to save time by replacing an often-used, sometimes lengthy, series of strokes with a shorter version. 2. In programming languages, such as C or assembly language, a name that defines a set of instructions that are substituted for the macro name wherever the name appears in a program a process called macro expansion when the program is compiled or assembled.

 Macros are similar to functions in that they can take arguments and in that they are calls to lengthier sets of instructions. Unlike functions, macros are replaced by the actual instructions they represent when the program is prepared for execution; function instructions are copied into a program only once.

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What is modem?

Short for modulator/demodulator. A communications device that converts between digital data from a computer or terminal and analog audio signals that can pass through a standard telephone line. Because the telephone system was designed to handle voice and other audio signals and a computer processes signals as discrete units of digital information, a modem is necessary at both ends of the telephone line to exchange data between computers. At the transmit end, the modem converts from digital to analog audio; 
at the receiving end, a second modem converts the analog audio back to its original digital form.

 In order to move a high volume of data, high-speed modems rely on sophisticated methods for “loading” information onto the audio carrier—for example, they may combine frequency shift keying, phase modulation, and amplitude modulation to enable a single change in the carrier’s state to represent multiple bits of data. In addition to the basic modulation and demodulation functions, most modems also include firmware that allows them to originate and answer telephone calls. International standards for modems are specified by the International Telecommunications Union, or ITU. 

Despite their capabilities, modems do require communications software in order to function. See also amplitude modulation, frequency modulation, quadrature amplitude modulation. Compare digital modem. 2. Any communications device that acts as an interface between a computer or terminal and a communications channel. Although such a device may not actually modulate or demodulate analog signals, it may be described as a modem because a modem is perceived by many users to be a black box that connects a computer to a communications line such as a high-speed network or a cable TV system.

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What is Internet domain?

Internet Domains

 In database design and management, the set of valid values for a given attribute. For example, the domain for the attribute AREA-CODE might be the list of all valid three-digit numeric telephone area codes in the United States.  For Windows NT Advanced Server, a collection of computers that share a common domain database and security policy. Each domain has a unique name. 3. In the Internet and other networks, the highest subdivision of a domain name in a network address, which identifies the type of entity owning the address for example, .com for commercial users or .edu for educational institutions) or the geographical location of the address for example, .fr for France or .sg for Singapore. The domain is the last part of the address for example, www.example.org. 

Top-Level Domains: Organizational

Domain	Type of Organization
.aero	Air-transport industry
.biz	Businesses
.com	Commercial
.coop	Cooperatives
.edu	Educational
.gov	Nonmilitary agency, United States federal government
.info	Unrestricted use
.int	International organization
.mil	United States military
.museum	Museums
.name	Individuals
.net	Network provider
.org	Nonprofit organization
.pro	Professional workers

Top-Level Domains: Geographic

Domain	Country/Region
.ac	Ascension Island
.ad	Andorra
.ae	United Arab Emirates
.af	Afghanistan
.ag	Antigua and Barbuda
.ai	Anguilla
.al	Albania
.am	Armenia
.an	Netherlands Antilles
.ao	Angola
.aq	Antarctica
.ar	Argentina
.as	American Samoa
.at	Austria
.au	Australia
.aw	Aruba
.az	Azerbaijan
.ba	Bosnia and Herzegovina
.bb	Barbados
.bd	Bangladesh
.be	Belgium
.bf	Burkina Faso
.bg	Bulgaria
.bh	Bahrain
.bi	Burundi
.bj	Benin
.bm	Bermuda
.bn	Brunei
.bo	Bolivia
.br	Brazil
.bs	Bahamas, The
.bt	Bhutan
.bv	Bouvet Island
.bw	Botswana
.by	Belarus
.bz	Belize
.ca	Canada
.cc	Cocos (Keeling) Islands
.cd	Congo (DRC)
.cf	Central African Republic
.cg	Congo
.ch	Switzerland
.ci	Côte d‘Ivoire
.ck	Cook Islands
.cl	Chile
.cm	Cameroon
.cn	China
.co	Colombia
.cr	Costa Rica
.cu	Cuba
.cv	Cape Verde
.cx	Christmas Island
.cy	Cyprus
.cz	Czech Republic
.de	Germany
.dj	Djibouti
.dk	Denmark
.dm	Dominica
.do	Dominican Republic
.dz	Algeria
.ec	Ecuador
.ee	Estonia
.eg	Egypt
.er	Eritrea
.es	Spain
.et	Ethiopia
.fi	Finland
.fj	Fiji Islands
.fk	Falkland Islands (Islas Malvinas)
.fm	Micronesia
.fo	Faroe Islands
.fr	France
.ga	Gabon
.gd	Grenada
.ge	Georgia
.gf	French Guiana
.gg	Guernsey
.gh	Ghana
.gi	Gibraltar
.gl	Greenland
.gm	Gambia, The
.gn	Guinea
.gp	Guadeloupe
.gq	Equatorial Guinea
.gr	Greece
.gs	South Georgia and the South Sandwich Islands
.gt	Guatemala
.gu	Guam
.gw	Guinea-Bissau
.gy	Guyana
.hk	Hong Kong SAR
.hm	Heard Island and McDonald Islands
.hn	Honduras
.hr	Croatia
.ht	Haiti
.hu	Hungary
.id	Indonesia
.ie	Ireland
.il	Israel
.im	Man, Isle of
.in	India
.io	British Indian Ocean Territory
.iq	Iraq
.ir	Iran
.is	Iceland
.it	Italy
.je	Jersey
.jm	Jamaica
.jo	Jordan
.jp	Japan
.ke	Kenya
.kg	Kyrgzstan
.kh	Cambodia
.ki	Kiribati
.km	Comoros
.kn	St. Kitts and Nevis
.kp	North Korea
.kr	Korea
.kw	Kuwait
.ky	Cayman Islands
.kz	Kazakhstan
.la	Laos
.lb	Lebanon
.lc	St. Lucia
.li	Liechtenstein
.lk	Sri Lanka
.lr	Liberia
.ls	Lesotho
.lt	Lithuania
.lu	Luxembourg
.lv	Latvia
.ly	Libya
.ma	Morocco
.mc	Monaco
.md	Moldova
.mg	Madagascar
.mh	Marshall Islands
.mk	Macedonia, Former Yugoslav Republic of
.ml	Mali
.mm	Myanmar
.mn	Mongolia
.mo	Macau SAR
.mp	Northern Mariana Islands
.mq	Martinique
.mr	Mauritania
.ms	Montserrat
.mt	Malta
.mu	Mauritius
.mv	Maldives
.mw	Malawi
.mx	Mexico
.my	Malaysia
.mz	Mozambique
.na	Namibia
.nc	New Caledonia
.ne	Niger
.nf	Norfolk Island
.ng	Nigeria
.ni	Nicaragua
.nl	Netherlands, The
.no	Norway
.np	Nepal
.nr	Nauru
.nu	Niue
.nz	New Zealand
.om	Oman
.pa	Panama
.pe	Peru
.pf	French Polynesia
.pg	Papua New Guinea
.ph	Philippines
.pk	Pakistan
.pl	Poland
.pm	St. Pierre and Miquelon
.pn	Pitcairn Islands
.pr	Puerto Rico
.ps	Palestinian Authority
.pt	Portugal
.pw	Palau
.py	Paraguay
.qa	Qatar
.re	Reunion
.ro	Romania
.ru	Russia
.rw	Rwanda
.sa	Saudi Arabia
.sb	Solomon Islands
.sc	Seychelles
.sd	Sudan
.se	Sweden
.sg	Singapore
.sh	St. Helena
.si	Slovenia
.sj	Svalbard and Jan Mayen
.sk	Slovakia
.sl	Sierra Leone
.sm	San Marino
.sn	Senegal
.so	Somalia
.sr	Suriname
.st	São Tomé and Príncipe
.sv	El Salvador
.sy	Syria
.sz	Swaziland
.tc	Turks and Caicos Islands
.td	Chad
.tf	French Southern and Antarctic Lands
.tg	Togo
.th	Thailand
.tj	Tajikistan
.tk	Tokelau
.tm	Turkmenistan
.tn	Tunisia
.to	Tonga
.tp	East Timor
.tr	Turkey
.tt	Trinidad and Tobago
.tv	Tuvalu
.tw	Taiwan
.tz	Tanzania
.ua	Ukraine
.ug	Uganda
.uk	United Kingdom
.um	U.S. Minor Outlying Islands
.us	United States
.uy	Uruguay
.uz	Uzbekistan
.va	Vatican City
.vc	St. Vincent and the Grenadines
.ve	Venezuela
.vg	Virgin Islands, British
.vi	Virgin Islands
.vn	Vietnam
.vu	Vanuatu
.wf	Wallis and Futuna
.ws	Samoa
.ye	Yemen
.yt	Mayotte
.yu	Yugoslavia
.za	South Africa
.zm	Zambia
.zw	Zimbabwe

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what is ANSI?

Acronym for American National Standards Institute. A voluntary, nonprofit organization of business and industry groups formed in 1918 for the development and adoption of trade and communication standards in the United States. ANSI is the American representative of ISO (the International Organization for Standardization). Among its many concerns, ANSI has developed recommendations for the use of programming languages including FORTRAN, C, and COBOL, and various networking technologies. See also ANSI C, ANSI.SYS, SCSI. 2. The Microsoft Windows ANSI character set. This set is includes ISO 8859/x plus additional characters. This set was originally based on an ANSI draft standard. The MS-DOS operating system uses the ANSI character set if ANSI.SYS is installed. 

Acronym for American National Standards Institute Standards Planning and Requirements Committee. The ANSI committee that, in the 1970s, proposed a generalized, three-schema architecture that is used as the foundation for some database management systems.  

An installable device driver for MS-DOS computers that uses ANSI commands (escape sequences) to enhance the user’s control of the console. See also ANSI, driver, escape sequence, install. 

A standard entitled “Representation for Calendar Date and Ordinal Date for Information Interchange” from the American National Standards Institute (ANSI) that covers date formats. Many organizations, including the U.S.   

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What is anonymous FTP?

The ability to access a remote computer system on which one does not have an account, via the Internet’s File Transfer Protocol (FTP). Users have restricted access rights with anonymous FTP and usually can only copy files to or from a public directory, often named /pub, on the remote system. Users can also typically use FTP commands, such as listing files and directories. When using anonymous FTP, the user accesses the remote computer system with an FTP program and generally uses anonymous or ftp as a logon name. The password is usually the user’s e-mail address, although a user can often skip giving a password or give a false e-mail address. In other cases, the password can be the word anonymous. Many FTP sites do not permit anonymous FTP access in order to maintain security. Those that do permit anonymous FTP sometimes restrict users to only downloading files for the same reason.

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Absolute pointing device

A mechanical or physical pointing device whose location is associated with the position of the on-screen cursor. For example, if the user of a graphics tablet places the pen on the upper right corner of the tablet, the cursor moves to the upper right corner of the screen or on-screen window associated with the pen. See also absolute coordinates. Compare relative pointing device.

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Why need calendar program?

An application program in the form of an electronic calendar, commonly used for highlighting dates and scheduling appointments. Some calendar programs resemble wall calendars, displaying dates in blocks labeled with the days of the week; others display dates day by day and enable the user to enter appointments, notes, and other memoranda. A day-of-the-week type of calendar program could, 
for example, be used to find out that Christmas 2003 will be on a Saturday. Depending on its capabilities, such a program might cover only the current century, or it might cover hundreds of years and even allow for the change . 
 
A calendar/scheduler program might show blocks of dates or, like an appointment book, single days divided into hours or half hours, with room for notes. Some programs allow the user to set an alarm to go off at an important point in the schedule. Other programs can coordinate the calendars of different people on the same network so that a person entering an appointment into his or her calendar also enters the appointment into a colleague’s calendar

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