When I write a song, musette creates two documents. First one with a suffix- .mus and the second one with a suffix -.bak. I wonder if the bak-documents are important.I already have a lot of them and I'd like to delete them. Can I do it without doing any harm?
You can safely delete bak files. When you save a file, the bak file is the original file before you made any changes. It provides a way to recover the original file if needed.