Pointers are variables that don't hold data themselves but instead hold a reference to it. It's really common to redirect pointers to reference something other than what they originally referenced, which is the joke in this comic. He is changing the conversation so that Star Wars actually refers to Jaws.

I personally don’t find it funny because these types of jokes essentially boil down to “I used a concept outside of its context, and for that reason alone it is funny”. However, with a lot of these jokes the context is so narrow (i.e. programming) that they are almost universally not understood by wider audiences.

To reference a movie in common vocabulary is to bring it up in conversation.

Referencing in programming terms like C refers to assigning a value to a variable. You can re-assign those variables to new values and then de-reference (read) the new value.

They are conflating the common meaning of reference with the much more obscure programming definition (obscure at least among non-programmers).

Star wars = "no, I am your father" (reference) Jaws = movie about hunting killer shark (reference) Star wars = movie about hunting killer shark (OP is pretending we can treat movie references like variable references and re-assigns the star wars variable to mean something else) "Hey, have you seen star wars? The movie about hunting a killer shark?" (De-referencing your newly re-assigned variable)