How do I show lines in vi or vim text editor?

To show lines in the vi or vim text editor, you can enable line numbers by using the following command:

:set number

This will display line numbers in the editor, and you can turn off line numbers by using the following command:

:set nonumber

Alternatively, you can enable line numbers when launching vi or vim by using the following command:

vi -c 'set number' filename

Where filename is the name of the file you want to edit.