What is a thought track in drama?

In drama, a thought track is a device used to reveal the inner thoughts and emotions of a character to the audience. It can take the form of a soliloquy, where the character speaks their thoughts aloud, or an aside, where the character speaks directly to the audience or to another character on stage, but is clearly not heard by the other characters. Thought tracks are often used to provide insight into a character's motivations and inner conflicts, and to give the audience a glimpse into the character's emotional life.