In Unix, how do I combine several text files into a single file?

To combine several text files into a single file in Unix, use the cat command:

cat file1 file2 file3 > newfile
Replace file1, file2, and file3 with the names of the files you wish to combine, in the order you want them to appear in the combined document. Replace newfile with a name for your newly combined single file.

If you want to add one or more files to an existing document, use the format:

cat file1 file2 file3 >> destfile
This command will add file1, file2, and file3 (in that order) to the end of destfile.

Note: If you use > instead of >>, you will overwrite destfile rather than add to it.