There is a standard set of terms to describe the parts of a character. These terms, and the parts of the letter they represent, are often referred to as "letter anatomy" or "typeface anatomy." By breaking down letters into parts, a designer can better understand how type is created and altered and how to use it effectively.
In the images below, the part of the character being discussed is in red, or circled in red. A few extra terms, such as baseline and x-height, are included to help understand and describe the letter anatomy.