Consider the case when you have a single large file and you have to transfer it via low capacity USB drive to another PC. You can not transfer it in one go. So you need to break it down into parts. So that one by one you can transfer its parts and after that join those parts back into single file after transfer. That file can be a video file, audio file, psd file or anything. If you download/upload at rapidshare then you know it is necessary sometimes to break big size file into small pieces/parts to transfer it somewhere. These parts can be joined later on for use. Recently I had to transfer a large file via USB device to another PC. Available resources included a File which was of 3GB and it needed to be transferred and I had 1GB size of USB device. Here is what I did.