Brecht was a playwright and theatre practitioner who explored theatre as a forum for political ideas, particularly with reference to his leftist beliefs.
He defied Aristotle's pillars of drama, and instead leaned into what is called "Epic theatre". The term was coined by Erwin Piscator, who heralded the concept alongside Brecht.
Epic theatre refers not the size or scope, but to the form that the work takes. It is a form of theatre that rallies against our expectations: it does not allow the audience to suspend their disbelief or get lost in the work, instead opting to keep them constantly aware of the fact that they're watching a performance.
Epic theatre put forth the idea that rather than evoking empathy and emotional connection with the characters, theatre should provoke self-reflection and a critical view of the action.
Brecht wanted theatre to give audiences a critical perspective so they may recognize social injustice, and to be moved to go forth from the theatre and effect change in the world outside.
One principle that Brecht employed was the "defamiliarization effect" or "distancing effect", which he described as "stripping the event of its self-evident, familiar, obvious quality and creating a sense of astonishment and curiosity about them".
He did through various techniques, such as the actor's direct address to the audience, harsh and bright stage lighting, the use of songs to interrupt the action, explanatory placards, the transposition of text to the third person or past tense in rehearsals, and speaking the stage directions out loud. These techniques are employed throughout Urinetown as well.