An Ascender is a part of a letter that extends and visually is at a larger height than other letters. For example an ‘f’ is longer in height than an ‘x.’
A Descender is a part of a letter that is visually larger and extends below the base of a letter such as ‘a’. For example ‘g’ extends down and is longer than the letter ‘a.’
A Baseline is a starting point used to measure and compare.
A Mean line is an imaginary line that may run across the top of non-ascending letters that have to be of lowercase category.
Kerning is the adjustment of spacing between different characters such as letters in a piece of text.
Leading is used to determine how text is spaced. Using vertical lines is commonly used to determine the size of the space.
Sans Serif is a simple typeface. When compared to serif you will be able to notice that sans serif does not have small ‘serifs’ at the end of points on letters.
A Serif is a projection or line, which may be seen at ends of letters depending on which typeface you may be looking at. (Depends on whether the typeface is sans serif or serif.)
Tracking involves changing and adjusting the spacing of the entire piece of text.