What does your computer do with data?

What is the context of the question? I hate to answer a question with a question, but the question is too broad to form an intellegent answer. If I had to answer the question as-is, I would say, it typically stores it on the Hard Disk Drive, or another mass storage device, like a Flash card, USB flash drive, etc. Hard Disks keep data on them after your computer is turned off. Anything stored in memory that is not written to the hard disk is lost when you turn off you computer.