Question

what is software?

Answer 1

Software is a collection of instructions that can be ‘run’ on a computer. These instructions tell the computer what to do. It is not a physical thing (but it can of course be stored on a physical medium such as a CD-ROM), it is just a bunch of codes.

An e.g. would be operating system such as Windows XP or Mac OS X, applications such as Microsoft Word, and the instructions that control a robot are all examples of software.

Answer 2

Short form:

Hardware is all the physical stuff that makes up a computer.
Software is all the non-physical stuff that does work using a computer.
Data is all the non-physical stuff that worked on by a software.