The ability of scanning beam x-ray microanaiysis to show the spatial distribution of elements was recognized quite early. At first it was done one element at a time by wavelength dispersive spectroscopy (WDS), but when energy dispersive spectroscopy was developed, that became the technique of choice. Because there have been several significant improvements in the technology, and also because maps are used so universally, I thought a review of the technology from the early days to the latest technology might be interesting. Though modern maps are ail digital, the original analog “dot” maps are used by a few even to this day. Other names for the technique are sometimes used such as “x-ray image”, which is correct but can be confused with radiography. Compositional image has also been used, but the term is broad and includes more than x-ray maps. Consequently, the universally recognized term “maps” will be used.