When it comes to copying files to and from your Android phone or tablet the normal way is to use a USB cable from your computer to your phone. It works absolutely fine that way but there's a few reasons why you'd want to have an alternative to the cable method. One alternative is WiFi transfer.
The first reason is that you don't have access to a cable. It might have broke, got forgot or even lost - or if you're like me then you might just be too lazy to go upstairs to get it haha - but if you don't have one then there is absolutely no way for you to use a cable to transfer your files.
There could even be problems with using the cable, for me my cable is too short to use without a USB extension. Or your cable port might be broken. I use a Galaxy Tab 10.1 as my primary Android device but the Galaxy Tab 2 10.1 came out last year if your looking to get a decent Android tablet.