HHVM or Hip Hop Virtual Machine has been ported over to the WordPress development crowd down to the core. HHVM was originally developed by Facebook as a way to curb expenses of more hardware for improved speed and reliability of server side php execution though a process know as JIT or Just In Time.
A Web Server is a computer system hosting web-centric applications and resources that is accessible through the World Wide Web.
This statement does not justify the Web Server as it is the meat of the Web. Web servers allow the internet to create gossamer links to bring forth the World Wide Web that we as spiders hunting for information or distraction click from link to link traversing a tangled web of electrons pushing and pulling through the internet landing on web servers near and far.
How Do Web Servers Connect?
With links of gossamer strands that you insert into your web presence. These links though have to provide directions to the correct server where the webpage we so desperately need resides.