y-
Hyphenate all words that begin with y used as a separate letter, such as y-coordinate and y-axis.
Don’t use italic formatting for the y in these words unless the entire word is italic.
y-axis
Use lowercase and hyphenate.
Don’t use italic formatting for the y in y-axis unless the entire word is italic.
y-coordinate
Use lowercase and hyphenate.
Don’t use italic formatting for the y in y-coordinate unless the entire word is italic.
YAML
Recursive acronym for YAML Ain’t Markup Language. Use uppercase.
Don’t use a filename extension to refer to a type of file. For example, use YAML file rather than .yaml file.
For more information, see Referring to file types.
