Missions can take up to two numeric parameters. Historically, these are called "I" (for Intercept) and "T" (for Tow), because they are used for the parameter to Intercept and Tow, respectively.
Client programs will prompt you for these parameters in some way when you set a mission that needs one.
Throughout the PHost documentation, we will use the "neutral" names "Parameter 1" and "Parameter 2" for the parameters.
