You could think of a database as a stack of filled out questionnaires. The electronic database has the ability to look down through the entire stack and immediately tell you how many people answered question 1 with a Yes and how many answered with a No. It can immediately decide how many were in each county or city, or area code, etc. In other words, the database is a stack of questionnaires which has the equipment built in to analyze the entire stack for any information you need.
For more information on databases and how to use them, check your local library, or see the operating manuals for any database software program. Usually, a simple database program comes with every computer, will be sufficient for your needs, and is not hard to learn.
See also, "record", "field", and "GIGO".