What is an ATS and how do I make an ATS friendly resume?

What is an ATS and how do I make an ATS friendly resume?

It is a software that is used by hiring companies to sort out the and rank the applicants. This system scans the resume based on job requirement. It search for keywords( key skills) required for job.
Best way to make ATS friendly resume is to mention those skills that are demanded by job. You should also ensure that important info is mentioned at proper place on resume sheet. ( ex- Projects should not be mentioned in the end). Make sure that you would not change bullets for every point, It should remain uniform and simple. Avoid writing unimportant information.