Building blocks of logic

Manas Paul
What is a logic gate especially where computers are concerned? A logic gate is an elementary building block of a digital circuit. Any arithmetic operation in a computer system can be implemented using basic logical operations. Three of the most common logical operations are NOT, OR and AND. Our phones have thousands, if not millions of logic gates. Everything from the CPU to the display screen to power management and alarm works on logic gates.

The Turing Machine: A blueprint for the computer

Subha Das Mollick
Did you know that the blueprint for a universal machine, one which had the simplest computing model and was powerful enough to calculate all possible functions was developed by Alan Turing, an English mathematician, logician and computer scientist? Turing showed that by inserting different programs in the memory of what he called the Universal Turing Machine, a computer could be made to carry out any task for which a program could be written. Today, we can see that Turing’s idea of a one-stop computing machine that can carry out multiple tasks was revolutionary.

Languages, symbols and people

Sudipto Bhattacharya and Subha Das Mollick
The earliest computers were programmed without a programming language. The languages were mostly codes based on decimal or binary systems. The next step was to devise a system to feed data into the computers. This was done through punched cards using Jacquard’s loom. The next big leap came in the early 20th century when the programming codes began to take the form of a language. The 1950s and 1960s saw the flowering of some of the modern languages like Fortran, Cobol and Basic that are still in use today. As of now, the evolution of programming languages continues both in industry as well as in research.


Computers have taken over our lives in more ways than one and it will not be an exaggeration to say that computers are the future , whether we like it or not. From checking bank balances to paying bills , computers have become a permanent fixture. In schools and colleges too, teaching and learning is now more computerised. This issue on computer science has a varied collection of articles on the subject that will help teachers look at the subject differently.

Teaching computing in schools

Madhavan Mukund
What exactly is a computer science class? Schools need to go beyond word processors and spreadsheets and teach students how to construct documents and effectively collect and organise data. Students need to be taught about security, privacy and ethics and to be responsible citizens in an Internet driven world. Basically the curriculum must be made more relevant to the students. Computing or computational thinking is what teachers should be teaching. Computing is about problem solving and at its core is the idea of an algorithm – about how to solve a problem. Teachers and curriculum developers need to think more on how this essential idea can be conveyed without disrupting the existing system.