Use mv to rename the file1.txt file to file2.txt, suitable for Linux
mv file1.txt file2.txt
mv [OPTION]... [-T] SOURCE DEST or: mv [OPTION]... SOURCE... DIRECTORY or: mv [OPTION]... -t DIRECTORY SOURCE... Rename SOURCE to DEST, or move SOURCE(s) to DIRECTORY.
I hope to help every developer quickly find the commands they need. Of course, you can also add your own commonly used commands for easy searching.