Apache Vs Nginx?

[turkey3]

This confuses me a bit since Vesta uses both these softwares. Which is the main one? What I mean is, do all requests on port 80 go through both Apache and Nginx, figuring out which one is meant for them, or does it all go through Apache which can redirect it to Nginx?

Also, Apache uses configuration files for its virtual hosts. Where are the Nginx virtual host files? Thanks! Just need some confusion cleared up.

[sim]

Apache serves dynamic files (php)

Nginx serves

jpg, jpeg, gif, png, ico, svg, css, zip, tgz, gz, rar, bz2, doc, xls, exe, pdf, ppt, txt, odt, ods, odp, odf, tar, wav, bmp, rtf, js, mp3, avi, mpeg, flv, html, htm

Apache is port 8080
Nginx port 80

configs are /home/user/conf/web

Start using google. This is not the place for newbie questions regarding WebServers.