https://benmccormick.org/2014/07/02/learning-vim-in-2014-vim-as-language
https://blog.carbonfive.com/vim-text-objects-the-definitive-guide/
In Vim, editing commands have the following structure:
<number><command><text object or motion>
The number is used to perform the command over multiple text objects or motions, e.g., backward three words, forward two paragraphs. The number is optional and can appear either before or after the command. The command is an operation, e.g., change, delete (cut), or yank (copy). The command is also optional; but without it, you only have a motion command, not an edit command The text object or motion can either be a text construct, e.g., a word, a sentence, a paragraph, or a motion, e.g., forward a line, back one page, end of the line. An editing command is a command plus a text object or motion, e.g., delete this word, change the next sentence, copy this paragraph.