Command File

From Fmepedia

A Command File is a way of using FME in a batch process. FME can be told to use a Command File from the command line. This will allow you to run multiple translations in sequence.

The difference between this approach and simply using several FME commands in a batch file is that when using a Command File, FME will not terminate between the translations. This will save you several seconds of start-up time per translation.

See this page for more details.