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Before going to the history let’s first understand the history of computer language. Earlier instructions were entered through front panel switches of computer. This was known as first generation language. Then in 1840’s Augusta Ada “The first programmer” suggested that a binary system should be used. From that time computer started understanding 0 & 1. Instructions given in this language is called machine language or assembly language first developed in the 1950s, which is nothing but symbolic representation of the numbers. Later it was found out that it was not user friendly & a slight error in the code use to be a huge setback for the programmers. Then something called compiler came into being.

As computer does not understand text language but only binary number, so a program was developed to convert the text language to machine language. This program is called compiler.

Towards the end of the 1950s, machine-independent programming languages were first proposed. Subsequently, several experimental compilers were developed. The A-0 system was the first compiler written by Grace Hopper, in 1952, for the  A-O programming language. The FORTRAN team led by John Backus at  IBM is generally credited as having introduced the first complete compiler, in 1957. It functioned more as a loader or linker than the modern notion of a compiler. Loader is the part of an operating system that is responsible for loading programs from executables into memory, preparing them for execution and then executing them. So we can say that the first compiler was developed with the help of assembly language. However these days we use Pascal, C ++,C etc.

Thanks to web 2.0! We have free online databases now!… Using Zoho, we can create database management systems which support SQL queries.

To create an online database, we have to register at http://db.zoho.com. Once registered, we can create database and tables by importing excel or from templates. The sql editor provided by zoho will allow us to generate and run SQL queries according to the needs.

An example online database system to find out returns and variance of stock markets is given here.

Father: What are you doing Shikha?

Shikha: Just booking a ticket over the internet.

F: Is it a very complex procedure?

S: No, papa it’s really very simple. As I can sit back at home and plan my journey.

F: And how will you cancel it?

S: Over the net.

F: I sometimes wonder how it functions!

S: For that one need to understand the basic architect of the Information System. We had a class on this taken by Dr.Prithwis.

F: Can you explain me the underlying architecture?

S: Why not… .ok…Just as you study the blue print of any building to understand the architect, one need to study the system architect model of the information system to see the flow of information. System Architecture deals with the database & application.

            Our desktop is a classic example of single tier architecture or integrated System in which both the database & application resides in the same machine. Our accounts clerk uses tally as an application and stores the database in different location within the same machine.

It is like having single large room for storing raw material & working (go down & workshop). Here it’s simple since there is only one user.

F: Ok

S:  But in large organization it’s not the case since there we have multiple users. There we can’t operate different database for different users, so we have one single database server and many application machines that can access that database server. It reduces cost as only one database needs to update and it reduces redundancy.

It’s like having a library and sharing the resource rather than each student having a separate set of books, as two students can land up having the same book.

F: In case of two tier architect how database & the application machine communicate?

S: Either through local area network (LAN) or wide area network (WAN) which you did in ICICI bank.

F: Ya I know.

S: Then we have a third type of architecture three-tier. In this we have separate database server, application server & many users.

F: So is this the one which they use in railway booking.

S: Yes. But they just have a separate feature attached since they have everything web enabled.

F: What is that?

S: The web server acts an interface between internet and client side applications. It enables you to access the Railway database and applications through internet. We just need to have net browser.

We just need to go to their web site through internet browser, fill the form which will go through the web server to the application server of the railways, and then to their database server to check the availability. Advantage is that to develop such architecture one needs to have many applications and as a user you are just using it.

A good example will be when you undertake some contract of construction you have various application like carpentry equipments, drill machine, cement mixture, workers etc. in place. Your clients know just that you are the engineers, who know what has to be done (database). You have will get the work done by your worker (application) & any interface between you and your client is the middleman (web server) which enables you to interact.

 F: I think I got a clear idea about the information architecture. Next time I will be able to use this booking application.