• Databases
• Front end Applications
• Network
• Operating Systems

DATABASES
What is involved in storing and manipulating data using computers? First of all we require software to store the data. This software is called a database. Databases are an important component of Information Technology. Databases could fall into three major categories:

• Flat files
• Relational databases
• Object oriented databases

Flat files databases were used in the 1970s and earlier years. In those days, there were no set industry standards to retrieve and manipulate data. Everybody had written their own complicated programs in C language to read and modify data in flat files. Examples of flat file databases are C databases, Fortran databases, and Pascal databases. In the 1980s, relational databases emerged on the scene. The only difference between the flat files databases and relational databases was that the relational database provided standard ways of querying and manipulating data which were missing from flat file databases. The industry adopted the SQL (Structured Query Language) as a standard language for querying and manipulating the data. Examples of relational databases are Oracle, DB2, Informix, and SQL Server. In the late 1990s, Object Oriented databases entered the I.T. market, however they did not gain too much popularity since they were unable to beat the data integrity provided by relational databases.

NOTE!
Do not confuse Object Oriented databases with Object Oriented languages i.e. JAVA which is a very popular language.

FRONT- END APPLICATIONS
Front-end applications are another component of Information Technology.

Storing the data and displaying it on the screen in a customized format are two different areas. The data is stored in databases. Employees of one department may want to use part of that data and perform some calculations on it, while employees of some other department may want to use some other data stored in the same database. Each department of the company, for example, would develop its own front-end applications to display data on the screen, to perform some calculation on it and then store the new calculated data back to the database, to run some reports on the data. Members of the other department could run a front-end application of their own to perform similar tasks. Therefore, we understand that each person or group of people can use different front-end applications to display the data of their interest from the database and to perform some calculations on it. Different users could connect to one database using the same or different front-end application. Front-end applications could be developed using tools or pure languages. Examples of front-end tools are Developer/2000, Visual Basic, JDeveloper, JBuilder. Examples of pure languages are C and Java. Building an application using tools is quick and easy, while building the same application using languages is a more resource consuming process. Tools are also built in pure languages themselves. They give you a quick start since all the basic work is already performed by them.

Some companies sell pre-built applications for specific operations with some room for customization. For example, Oracle Financials and SAP are two famous Enterprise Resource Planning (ERP) applications which an organization may install and implement in order to perform its accounting tasks on a big scale, rather than developing its own accounting application. Another example of pre-built applications is Retek, which is used by retail stores. Both Retek and Oracle Financials are built using Developer/2000, while SAP is written in C. Front-end applications can be written for the web. Java is mostly used for this purpose. E-commerce applications are an example of web enabled front-end applications.

NETWORK
Database is installed on a powerful computer because many people access it simultaneously. This computer is called a Server. In order to access the database you do not necessarily have to use the Server computer where the database is installed. You can access the database through any computer where your front-end application is installed. The front-end application will then connect to the Server computer to access the database through a network. Therefore, networking is another component of Information Technology. Networking technology consists of both software and hardware. Novell networking, CISCO and NT networking are big names in this field.

OPERATING SYSTEM
All the software including databases and front-end applications are installed on an operating system. Therefore managing an operating system is also an important task for a company. Operating systems form another important component of Information Technology. Usually databases are installed on a secure operating system like Unix, while front-end applications are installed on an easy-to-use operating system like Windows which can provide Graphics User Interface (GUI). Linux is another operating system which is immensely popular nowadays. It is a secure system like Unix and provides Graphics User Interface like Windows, and most of all ... it is free.