Unlike most other editors, when you enter Vim, the characters you type in the default state are not inserted into the file you are editing. The concept of Vim (mode, which can simply be understood as "state") is very important. You need to know that Vim has the following modes:1)Normal mode, the default editing mode, the following without special instructions, the mentioned commands are directly entered in normal mode, any other mode can be returned to normal mode by the ESC key on the keyboard.2)Command mode for longer, more complex commands, enter ":" In normal mode (General command), "/" (forward lookup), or "?" (Reverse lookup) to enter the mode, command mode commands to enter the return (enter) is not complete.3)Insert mode, use when entering text, type "I" (insert) or "a" (append) in normal mode to enter insert mode (some other commands, such as "C", can also go into insert mode, but these commands have other effects).4)Visual (visual) mode for selecting text blocks, you can enter "V" in normal mode (lowercase) to select by character, enter "V" (uppercase) to select by row, or enter "Ctrl-v" to select by a square.5)Select (select) mode, which is closer to the normal Windows editor to select a block of text, and after selecting a block of text in one of the visual and selection modes, you can use "ctrl-g" to switch to another mode-the pattern is rarely used on Linux and is no longer covered in this article.
There are several modes of VIM:
