The text talks about "Apache for Linux, and IIS for windows", but should probably mention that google.com is probably not using those (it's probably using Google Web Server https://en.wikipedia.org/wiki/Google_platform#Software at some level).
But I think when we talk about what the server side does we should treat it as one of these other options because then we can go into details about how the innards of the server side works.
The text talks about "Apache for Linux, and IIS for windows", but should probably mention that google.com is probably not using those (it's probably using Google Web Server https://en.wikipedia.org/wiki/Google_platform#Software at some level).