It should state where and when errors in IO are detected and how they will be dealt with. The architecture should state how errors of any kind will be handled. It should state the whether an error should be corrective or merely detective. The program can correct an error or it can stop processing once an error has been found. In any case it should let the user know an error has occurred.
Construction is the process of actually writing the code that makes a program.
This is what you thought you were going to deal with in these classes, and you were right. There are certain things you should know up front, and this lesson tries to cover them. We will get into construction in great detail later. System testing is the quality control portion of the project life cycle. You probably thought of system testing in the past only in the terms of BETA testing you may have heard about by the big software houses.