Spider-Man is traditionally depicted as using mechanical web-shooters created by Peter Parker, which are worn on his wrists. These web-shooters allow him to shoot webbing at will, which he uses for swinging between buildings, trapping enemies, and creating web-based constructs. The design emphasizes his intelligence and scientific prowess, showcasing that he is not only a superhero but also an inventor.
In some adaptations, particularly in the early comic issues and certain films, Spider-Man's powers have been depicted as organic, suggesting that he can shoot webbing directly from glands in his wrists or palms, similar to how a spider produces silk. This portrayal aligns with the more naturalistic aspects of his abilities following his spider bite, allowing him to have web-shooting capabilities without mechanical devices.
The choice between these two portrayals often comes down to creative direction and the themes an adaptation wants to emphasize, whether it's Peter's ingenuity and reliance on technology or the biological transformation that came with his superpowers. In essence, the mechanical web-shooters represent Peter's intellect and ingenuity, while the organic webbing reflects a more direct connection to his spider powers.