In typography, the upward vertical stem on some lowercase letters, such as h and b, that extends above the x-height is the ascender. The height of the ascenders is an identifying characteristic of many typefaces.
The ascenders of some letters may touch or almost touch letters in the line above causing awkward or distracting patterns. This is most likely to happen or be obvious when a line of text with tall ascenders is below a line of text with long descenders. To resolve the problem of touching ascenders and descenders you can: