The Glass Menagerie is described by the playwright, and by Tom Wingfield, the narrator, as 'a memory play'. Therefore, it is not meant to be a straightforwardly realistic representation of events, but rather a collection of scenes that is constructed through remembrance.
The fact that this is a memory play - drawing on the playwright's own life - has important consequences for its style. For example, at the very beginning when the Wingfield family are shown at dinner, the actors are simply meant to mime the gestures of eating, without any actual dishes on the table. The play is concerned less with such routine details than with artistic concerns like the use of symbolism, lighting and music to represent the essential quality of Tom’s remembrances.
The playwright also draws attention to the play’s artifice by use of a screen device which flags up important aspects of a scene to the audience. For example in scene five when Tom reveals to Amanda that they are going to have a gentleman caller, at long last, the word 'Annunciation' is put up on the screen as the scene opens, and then, at the moment of Tom’s announcement, there is an accompanying image of ‘caller with bouquet’ and a burst of music.
The theme of the family is perhaps the predominant theme in this play. This includes family conflict (particularly Tom and Amanda’s quarrels), family duty (the burden placed on Tom to provide for his mother and sister in the wake of his father’s desertion), and the tension between family duty and duty to oneself (Tom longs to be free in order to follow his own path).
Another important theme is that of daydream and illusion. All the Wingfields live in a make-believe world of their own to some extent, most of all Laura who generally appears immersed in the world of her little glass animals and constantly plays old 'worn-out records', as Amanda disapprovingly notes (scene 4). Amanda meanwhile attempts to escape to the happier world of her past while Tom concocts romantic imaginings about a future life of freedom and adventure and also seeks vicarious excitement at the cinema.