Abbreviations are often used in chord names (alternative chord symbols in parentheses).
E - E major (E△)
Em - E minor
E7 - E dominant seventh
Em7 - E minor seventh
Emaj7 - E major seventh (E△7)
E6 - E major sixth
Em6 - E minor sixth
E6/9 - E sixth/ninth
E5 - E fifth
E9 - E dominant ninth
Em9 - E minor ninth
Emaj9 - E major ninth
E11 - E eleventh
E13 - E thirteenth
Eadd - E add
E7-5 - E seven minus five
E7+5 - E seven plus five
Esus - E suspended
Edim - E diminished (E°)
Em7b5 - E minor seventh flat five (Eø)
Eaug - E augmented (E+)