What are the subjects to study ?
As per previous year question papers they seems more interested into the following subjects.
- Operating System
- Computer Networks
- Programming in C / Data Strcuture
- Compiler Design
- Digital Logic
- Databases (Mostly SQL queries and normalization)
I have given the order in which you may prepare for the exam. (just recommendation not necessary)
What sort of questions to practice for the exams ?
ISRO will also provide last few year papers. Practice it to know speed since there will 90 minutes for 80 questions so speed matters here.
Let me generalize few things with my experience (not much but still whatever i have figured out till now). There are two category of exams like
- Other Exams for PSUs/SAIL/HAL/Others
In GATE/TIFR you will always get new question so to solve this you need to know the concept thoroughly and rest all other exams like PSUs/SAIL/HAL/Others,they directly ask the GATE/TIFR question. So for preparation of any such exams, you need to solve GATE question before solving anything else.Its only because here speed matters and there are high chances that you will get "GATE 1/2 marks question" as it is. So sometimes when you will be running out of time then it will be advantageous for you marking the answers directly and getting 2 marks without wasting much time in solving :)
Warning : Don't directly marks the answer unless you are confident about the question and its answer Since there is negative marks in case of ISRO.
PS: Its enough to solve the GATE question with complete understanding for the ISRO exam :)