When a model and photographer (and sometimes a make up artist (MUA) too) work together, either to enhance their technical and creative skills or simply to add to their portfolio.
Similar to a test shoot, TFP (time for photographs) or TFCD (Time for CD) each party provides time in exchange for prints or images. Generally offered by those who are transitioning into a new area of photography or trying to build their portfolio of work but also good for trying out a new style, experimenting with some new equipment or simply helping others out.
TFPModels is about learning and improving together. Add as much info to your profile as you can, along with some recent photos. Post in the forum and see who is interested in working with you. Ask a question if you're new to modelling or photography. See who else is here that you might want to work with. Share ideas. Build that portfolio.