MPT and FPT are simply names for identifying the type of pipe thread for an application.
Math Tools - Pipe Diameters, Threads and Sizes
Pipe Sizes Information
Understanding NPT and Other Pipe Thread Types
Everything You Need to Know About Pipe Thread Sizing - Spotix Blog
Pipe Thread Acronym Definitions
Everything You Need to Know About Pipe Thread Sizing - Spotix Blog
NPT Thread & NPT Thread Size Chart - Runsom Precision
Types of Pipe Threads NPT, IPT, Compression-Thread differences
Math Tools - Pipe Diameters, Threads and Sizes