Context: As you probably are aware, a bicycle typically has two sets of gears—one at the front and one at the rear. For example, a "3×5" bicycle has three front gears and five rear gears, for a total of 15 effective gear ratios (or fewer than 15, since some may overlap with each other). However, in recent years improvements in derailer technology have made it possible to simply shove all the gears into the rear set and eliminate the front derailer. This is known as a "1×" gear configuration (pronounced "one-by", and meaning "one front gear and some large number of rear gears"). Having only a single set of gears makes shifting simpler and can cut down on mechanical problems.