This seems like a nice introduction guide to caching but it seems a bit dated.

It does not mention using varnish, memcache, redis or anything similar. And it talks of CGI scripting being one of the most popular ways to generate content.

Written in 1998. Go, ColdFusion!

But I've found a lot of current devs are missing some of the basics that folks used to have to know so it doesn't hurt to talk about HTTP response headers and the like every now and then.

> Written in 1998.

And I assume that we're seeing a cached version of the site, which is probably the joke.

Yep, I stumbled over it while researching the Cache-Control header.

It doesn't mention Varnish because it didn't exist back then. But he mentions reverse proxies: http://www.mnot.net/cache_docs/#GATEWAY

It does not mention Squid either. It does not mention varnish because it is about HTTP caching in general.