Greek writers signified by “lyric” a song rendered to the accompaniment of a lyre. The term is now used for any fairly short, non-narrative poem presenting a speaker who expresses a state of mind or process of thought and feeling. Lyric speakers may be represented as musing in solitude. Although the lyric is uttered in the first person, we should be wary about identifying the “I” in the poem with the poet. In many poems, the speaker is clearly not the author but an invented character, and one who may be very different from the actual poet.
On the other hand, "epic" is applied to a work that meets at least the following criteria: it is a long narrative poem on a great and serious subject, told in an elevated style, and centered on a heroic figure.