How to save changes to a file in CentOS?

After making changes to a file in CentOS, you can save the file using the following methods:

1. To edit with vi or vim:
   a. Open the file using vi or vim command, for example: vi file.txt.
   b. Make modifications in the editor.
   c. Press the Esc key, then type :wq to save and exit.
2. To edit with nano:
   a. Open a file using the nano command, for example: nano file.txt.
   b. Make modifications in the editor.
   c. Press Ctrl+O to save the file, and then press Ctrl+X to exit the editor.
3. Using the echo command:
   a. Redirect content to a file with the echo command, for example: echo “Hello, World!” > file.txt.
   b. This will overwrite the original file content, if you need to append content instead of overwriting, you can use the >> operator, for example: echo “New line” >> file.txt.

Regardless of the method employed, it is essential to ensure that there are sufficient permissions to modify the file.