How to append to existing file?

To append content to an existing file using the cat command, you can use the following steps:

1. Open your terminal.

2. Use the following command:

   cat >> existingfile.txt
   

3. After running the command, you can start typing the content you want to append to the file.

4. Once you are done, press CTRL + D to save and exit.

This will add the new content to the end of existingfile.txt without overwriting the existing content.