You can mention the developer, the designer, the copywriter, the webmaster, the SEO, SEM or SMO…
As you can see, the number of people who may take part of the creation of a site can be big, so the list is almost endless.

Humans TXT is an initiative for crediting the creators of a website. It’s very simple: just add a custom .txt file to the site root that delineates the author(s) of the site. You can check mine here.