These guys (mostly guys) write and type code. They also create software programs typing these codes. They're the middle man for software developers to make their designs understandable for the computers.

A researcher try to improve and create new technology. They solve problems for business trying to use technology.

What does a computer researcher, programmer, and a software developer do?

Researcher. Programmer. Software Developer

Using their creativity they create software that allow users to do a specific task on any device.