Anyone who has seen a photo of themselves taken from behind will recognise the speaker's shock. He is caught by someone's camera with his back turned, and he can hardly believe the balding, grey-wisped head on the screen belongs to him. He describes it with blunt, funny images: stray hair like an "odd-looking horseshoe" stuck on a scalp that shines back the camera flash.
Beneath the humour is something more unsettling. The speaker has spent his whole life knowing only his front, the face in the mirror, which he thinks he knows well. The back of his head is a part of himself he can never look at directly. The final lines, "a view of myself that I will never see / with my own eyes," turn the joke into a quiet reflection on how little of ourselves we can really observe. The mood begins wry and self-mocking, then settles into a thoughtful, slightly uneasy acceptance that other people see us differently than we do.