I have a question relating to barre chords. I know that there are different shapes for barre chords (eg E shape and A shape) What is the point of having different shapes? Cant you play any song with the E shape using major and minors? Why would you use one shape over another?

Sorry if this is obvious but I cant really think of a reason unless it is just to keep the chords close on the fret board.

thats exactly what it is, to keep the chords close on the fretboard so its easier to switch from one chord to another and faster as well.
Great thanks!! Does it have anything to do with octives as well or is it just swiching from one to another is easier then going way down the neck to get to another chord?
Just the switching thing.
Quote by scottishmob

This is a site for musicians and you're all crying about the sad state of rock? Fuck that. I'm going to practice more and take over radio. I advise you all to do the same.
Different voicings will sound slightly different. Also you can add different embellishments to different shapes, and they'll sound diffent when playing arpeggios.
Fender Classic Player 60s Strat
Washburn HB35
PRS Santana SE
Yamaha Pacifica 112MX
Vox AD30VT
Fender Champion 600
Dunlop wah
Danelectro Cool Cat fuzz
These 5 open chords CAGE & D (played w/o a barre on the first three frets) can be repeated all the way up the neck if you then barre them as you move on up the neck. They're pretty hard to master as you have to train your pinky, ring, and middle fingers to play chords while barring with your index finger.

There's a really good book on this technique called Fretboard Logic by Bill Edwards but if you can do it physically you'll kickass.

He also takes this method and builds scaleforms from them.

Good Luck
also, the E shape barre has the root on the 6th string. the A shape barre has the root on the 5th string.

playing a E shape barre on the 15th fret (for a G chord) is abit awkward. so, you can play the A shape barre on the 10th fret, which is more comfortable.

just a thought.