Many commands have several options. For example, you can specify CIRCLE as (1) center point and radius, (2) two points on the diameter, or (3) three points on the circumference. The first prompt asks for the construction technique (3P/2P/<Center point>). You can specify the center point (the default) immediately. For the two point or three point technique, specify 2P or 3P.
You can abbreviate the options. Type enough characters to make the selection unique. For example, in the CIRCLE command options, the choices are 3P, 2P, and Center point. Typing 3 is enough to specify 3P, and 2 to specify 2P. You do not need to specify Center point since it is the default and accepts point data.