The most important user-defined type is the record, which combines different built-in types within it. A record will store data about an object, person, event etc. and arrays of records can readily be saved to a file of records to be stored on disk. The first part of the tutorial covers single records, which are easier to code than the arrays of records that you will be likely to use much more frequently.
Continue with the following topics to learn more about this important area of programming: