The Glass Menagerie can be easily explained as an example of a memory play in its basic taxonomy, the manner in which the scenes are coordinated, and the way in which the main character relates the series of events.
A memory play similar to a stream of consciousness story in that the main character is relating facts as he or she remembers them. In this case, Tom was relating his experiences in and out of the play as they occurred and, in the end, told us what he hoped would become of his mother and sister.
In the same line, the play is performed under an almost surreal light as if ALL of it were a memory. This is what makes some of these plays so extraordinary and entertaining to watch. Finally, a memory play employs a language that reflects the personal views of the main character, and gives us a chance to look within the feelings and emotions of the character in a deeper and more engaging way.
I think that there is a dominant presence of memory and the role it plays in Williams' work. Its function is clearly seen in Amanda. Her reminiscing of the past, how she was in her own memory, helps to make everyone feel uncomfortable. Memory is used as a device of oppression in that Laura is made to feel inferior because her present does not match Amanda's past. In her fantacizing of the past, it also serves to oppress her because she cannot effectively deal with the chasm between the supposed grandeur of what used to be and the barrenness of the present. Additionally, such an inability to grasp both domains is what ends up helping drive Tom away. In a larger sense, Amanda's obsession with memory is a reflection of her obsession with the subjective. This is something with which all of the characters are afflicted. Each character seems to believe that Laura is stuck in her "own world" and her own subjectivity. Williams' genius is to actually make this an affliction that Amanda, Tom, and even Jim, to a certain extent, suffer from, while Laura, the one whom everyone thinks is really afflicted, is actually the least cursed with such a condition.