An ABL procedure is made up of blocks. The procedure itself is the main block of the procedure. There are a number of ways to define other blocks within the main procedure block. The FOR EACH statement and its matching END statement are one example of a nested block, in this case one that iterates through a set of database records and executes all the code in between for each record in the set. There are other block statements you can use for different purposes. Some of them are also iterating, and cause the block to be executed multiple times. Others simply define a set of statements to be executed together. You'll learn about all of these in later chapters.