The actual commands of the user to SWAN must be given in one file containing all commands. This file is called the command file. It must be presented to SWAN in ASCII. It is important to make a distinction between the description of the commands in this User Manual and the actual commands in the command file. The descriptions of the commands in this User Manual are called command schemes. Each such command scheme includes a diagram and a description explaining the structure of the command and the meaning of the keyword(s) and of the data in the command. The proper sequence of the commands is given in Section 4.2.