Both poetry and drama are considered literary genres. Poetry is written form that expresses emotions, observations and feelings through rhythmic cadence. It is this combination of cadence and words that draws the reader or listener in. Drama, by contrast, presents the actions and words of characters on the stage. The intensity of action and plot development are the key markers that act to draw the viewer in.
Perspective is key when considering the differences between poetry and drama. In the lyrical sense of poetry, the poet writes from his perspective. He will often employ first person use of "I," or will write from the role of personal observation. Drama, even when written from personal experience, includes characters that are separate from the writer. The writer must create an external way of expressing himself within plot and this is seen through actor monologues or by the voices of multiple stage characters.
Each genre has a particular style. For example, poetry presents a clear rhythmic form. It is the mind of the poet that chooses the cadence. The poet chooses words which have a particular syllabic breakdown to establish a rhythm. Poetry can be abstract and have different meanings to the reader. Drama, on the other hand, must have the action of characters around plot choices such as irony and conflict. Without plot, the story has no form to lead and draw the the viewer's attention. This leaves less room for drama pieces to be abstract.
Commitment to Form
As a writer of either genre, you must become familiar with the forms of your genre and be faithful to artistically crafting works within these forms. Creativity is fine, but you must abide by the established form expectations. For example, the poetry form of a sonnet is only 14 lines long. It would be nearly impossible to write a drama with such a format. In contemporary drama, flashbacks, scenes, setting changes and sequencing jumps are employed. This would be difficult in poetry and does not fit its form.