I will only give a brief usage example. For more information, check out man split (and info coreutils 'split invocation' on Linux).
You split a larger file into smaller ones issuing a command such as:
split -b 100M your.fileThe command above will split your.file in 100 megabytes volumes, called by default "xaa", "xab", "xac" and so on.
If you feel you need another "pattern" or prefix, add that string to the end of the command:
split -b 100M your.file file.part.
The above command will split your.file in volumes called "file.part.aa", "file.part.ab" etc. (instead of the default "xaa", "xab" etc.).
If you prefer the suffix (the "increment") to be digits rather than letters, use the -d flag.
split -db 1G your.file file.part.
would produce volumes of your file of exactly 1 gigabyte, called "file.part.00", "file.part.01" etc.
To join the volumes, it is this simple:
cat `echo file.part.* | sort` > your.file.reloaded
Both your.file and your.file.reloaded have the same MD5 sum – they are identical.