Vim's visual mode allows for an arbitrary selection of text (usually to perform some sort of operations on). It's useful when you want to work with a section of a file that does not map to an existing text objects (word, sentence, paragraph, and so on). There are three ways to enter visual mode:
v enters a character-wise visual mode (status line text: -- VISUAL --)
V enters a line-wise visual mode (status line text: -- VISUAL LINE --)
Ctrl + v enters a block-wise visual mode (status line text: -- VISUAL BLOCK --)
Once you enter visual mode, you are able to move your cursor using the usual movement commands, which would expand the selection. In the following example, we've entered a character-wise visual mode ...