What is it called when writers are editing capital letters numbers and abbreviations?

There isn't one specific term for editing capital letters, numbers, and abbreviations. However, depending on the context, you could use these terms:

* Proofreading: This is the most general term and refers to checking for any errors in a text, including capitalization, numbers, and abbreviations.

* Line editing: This focuses on the overall clarity and flow of the writing, which can include checking for inconsistencies in capitalization, number format, and abbreviation use.

* Copyediting: This involves refining the language and style of a text, which often includes correcting errors in capitalization, numbers, and abbreviations.

* Style editing: This focuses on ensuring the text adheres to a specific style guide (like AP Style or Chicago Manual of Style), which would dictate the correct use of capitalization, numbers, and abbreviations.

Ultimately, the specific term used will depend on the specific type of editing being done and the context in which it is being performed.