Hard is the second hardest difficulty in the Guitar Hero series. While it uses all five fret buttons, its note patterns are not as difficult as Expert, and most songs are easily Full Combo-able to an experienced Expert player. Hammer Ons and Pull Offs are not as common in Hard (and there are fewer streaks that last for several hundred notes.
Gameplay Elements to Make Hard Harder than Medium
One of the most noticeable additions is the use of the orange fret button. While the learning curve was less steep in Guitar Hero, the curve was steepened much more in Guitar Hero II. There are also more chords in Hard, and split chords (Green and blue notes and Red and Orange notes) begin to appear. There are also rare three note chords on this difficulty. With Neversoft's new system for Hammer-Ons, there are several 16th notes in Guitar Hero III that would have been Hammer-Ons with Guitar Hero II's game engine, but with their new engine, they are made to be strummed. In Guitar Hero: Aerosmith one song has a 3 note chord.
Hard