A E Augmented (Eaug) chord contains the notes E, G#, C. It is built from the augmented formula 1 - 3 - ♯5, with E as the root.
When would I actually play an E augmented chord?
Most often as a connector. Going from E major to A minor, swapping in Eaug for a beat pushes the B up to C so the melody arrives on the next chord's root instead of jumping to it. The same trick works heading into C major. It's a colour you pass through, not one you linger on.