E5 is a power chord chord made of 2 notes: E, B. It sounds strong and neutral, with no third to make it major or minor, and you hear it in rock, punk and metal, especially with distortion. It is the I chord of E major and turns up in 5 other keys.
The library above opens on E5 with 14 shapes up and down the neck, starting with hand-checked ones. Tap a shape to hear it, or play it one string at a time.