Think of 'prototypical' as the ideal or most common version of something in a group. The prototypical superhero has superpowers and a secret identity.
Pro Tip 2/3
Basis for Others
'Prototypical' refers to something that serves as a reference point for similar things. The prototypical smartphone design influenced many later models.
Pro Tip 3/3
Cultural Stereotypes
In culture, 'prototypical' may describe common features of a group often overstated in media. She was cast as the prototypical villain with a dark cape and sinister laugh.