"wiki" refers to a website that allows users to add map content and then share that content with others.
Wikiloc I will be using Wikiloc to post the horseback trails on Portneuf River Back Country Horsemen. Unlike CalTopo, Video and Pictures can be added, a driving map to the trailhead can be created, and a GPX trail map file can be downloaded. It also has iPhone and Android Apps.
This is my newest discovery, a 3D Slippy Map like Google Earth. The benefit of FATMAP is that it is viewed in your browser instead of being a separate program like Google Earth.
All of these map pages are produced by Recreational Equipment, Inc., commonly known as REI, is an American retail and outdoor recreation services corporation.