Hello, I'm an expert in the field of comic book lore and superhero characteristics. When it comes to Spider-Man, one of the most iconic aspects of his abilities is the substance he can shoot from his hands.

Spider-Man, a character created by writer Stan Lee and artist Steve Ditko, has the proportionate strength of a spider and the ability to cling to walls, among other powers. However, one of his most distinctive features is his web-slinging ability.

Spider-Man originally had the ability to spin his own web due to the bite of a radioactive spider. This was depicted in the early comics and the 1967 animated series. However, in later iterations, particularly the movies and some comic book storylines, it is established that Peter Parker, Spider-Man's alter ego, creates a device called a web-shooters to emit artificial web fluid that he designs himself.

So, to answer your question, Spider-Man shoots out artificial web fluid from his hands, which is emitted through a device known as web-shooters.

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In "Disassembled", Spider-Man develops the ability to shoot organic webbing from his wrists (after he recovered from being changed into a spider), and he stopped using his Web-shooters which was a great advantage for him because it allowed him to stop being dependent on web cartridges which allowed him limited shots.read more >>