To ask is to pose a question or request something. If you say "What time is lunch?", then you're asking a question.
You've probably heard people say "Can I ask you a question?" That pretty much sums up what asking is: trying to get information or make a request. A teacher asks students to answer questions, but a student has to ask the teacher for permission to use the bathroom. In business, the asking price is the amount the seller wants you to pay. Asking is how you find things out and get what you need.