Serifs are the small tick-like lines at the end of character strokes. Every letter in a serif font includes serifs. The serifs assist the eye to read the text. A sans serif font doesn’t have serifs and is typically used in headings and titles.
Kerning and tracking are two terms that are easily confused because they both refer to the adjustment of space between type and type-related characters.
Kerning is the deliberate and selective spacing of letters. The space between letters can be adjusted to create a more even appearance or to affect the overall density of a text block. Tracking is the adjustment of space between groups of letters and entire blocks of text.
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Kerning changes the space between a couple of letters and tracking affects the space between all letters.
Sometimes when you place certain letters together they can create an awkward space. You will notice this more so when working with capital letters and creating a title for a promotional presentation such as a poster. Kerning, whether adding or subtracting space between letters, can assist in creating a more aesthetic and readable text.
The letter combinations at the right, depending on the design situation, may need kerning.
When to track
Tracking can make your text appear more open or denser and just like kerning tracking can change the overall appearance and readability of your text.
You can apply tracking to all of your text or selected portions depending on your needs. For example, you might use selective tracking to get more characters onto a line to save space or prevent a few words from carrying over to another page or column of text.
Leading is the amount of space between the lines in a text. It is measured from one baseline to another baseline. The leading can greatly affect how readable your text will be. When the leading is decreased, your lines of letters may appear more compact; whereas, too much leading can relax the eye and cause continuity problems. It is called leading because thin strips of lead were placed between lines of metal type with the old style of letterpress printing.
There is a set of terms used to describe different parts of a letter. Sometimes these terms are referred to as typeface anatomy. If we break down letters into parts it makes it easier to understand how a letter is created, to make observations and alterations and use it more effectively. Terms that you should be aware of are: x-height, ascender, descender, baseline and cap height.