What is the difference between "work on computer" and "work on the computer"?

Question

I have heard people say both work on computer and work on the computer. For example:

I work from home because I work on computer.

I work from work because I work on the computer.

Is there any difference in meaning between the two? If there isn't any, then which one is more common?

Answer 1

The first is possible but not idiomatic.

The second is better, assuming you meant to write:

I work from home because I work on the computer.

But really I’d expect to hear other versions like:

I work from home as my work is all on the computer.

I work from home because all my work is all online.