The basic idea here is the same as ever - presented with a track stretching into the screen, notes will slide down the track towards you in one of three columns, and it's up to you to hold the relevant button on the guitar's neck, and strum as it passes a line at the bottom of the screen. Miss the notes, and the guitar part will stop playing - but hit them, and you'll feel like a rock god. Unlike Rock Band, which lets up to six people play together co-operatively, Guitar Hero Live only lets two people play in a competitive multiplayer mode, which requires an extra guitar (sold separately).
Guitar Hero Live also has a strong online component - and not one that necessarily sees you facing off against other players directly. Instead, the game is divided up into two sections - on the disc, there are 42 tracks that you can play at will, while the online side of things is called Guitar Hero TV. This offers two, free "24 hour music channels" that you can drop into and start playing along to music videos on. The catch is, while the songs are free, you don't have any say over what you're playing, with the selection of tracks instead being chosen depending on what "program" is on at that time, whether it be classic rock, emo or metal. If you want to play a specific song, you'll have to spend a "play", which you can earn (very slowly) by playing Guitar Hero TV mode - or, you can buy with real cash. There's no way to buy an unlimited amount of goes on songs on Guitar Hero TV, or unlock a song permanently.
With five difficulty levels on offer, you can tailor the challenge to suit, with the easiest difficulty level offering a suitably shallow learning curve for newcomers, and only the odd note to play every few seconds. The three lowest difficulty levels only actually make use of one row of buttons, with advanced and expert being the only place you'll be asked to move your fingers up and down, as well as from side to side. Letting you play bar chords (holding black and white at once), split chords (holding two black or white notes), as well as individual notes, the new 3x2 layout provides a great scalable difficulty level that really helps make things easier for kids to pick up and play. That said, with the guitar being large, and requiring a fair amount of manual dexterity, this is probably best suited for older kids.