A loom is a mechanical machine typically powered by human hands (and feet). Looms can be as simple as the ones you may have used in childhood to create potholders or so complex they're programmed and powered by electricity. Machine in Hand uses to fully manual floor looms—a 4 shaft and an 8 shaft.
First Things First
Before you even begin to use a loom, a lot of planning—and math!—goes into the setup. You need to determine your pattern, which is limited by the type of loom and the number of shafts you have available, calculate width, length, ends per inch for density, and much more. Because set up is so time consuming and labor intensive, you rarely set up your loom for a single piece. (Unless perhaps it's one very large piece, like a chuppah cloth.) When Machine in Hand decides to make new tea towels, for example, I create a warp long enough to produce approximately 15 towels.