A procedure abstracts an operation
An example shows how the operations that make up your morning routine can be abstracted into a series of separate "procedures".
A second example shows some real Ada procedures without parameters. It shows how the operation of drawing the word "ADA" in giant letters can be separated into separate procedures for drawing an "A" and a "D". You can see how the program is broken up into procedures, and how they are called upon to do their task.
A third example shows some procedures using parameters. It shows how procedures improve the modularity and clarity of the whole program.