Isn't Squid like, 5 or 6 years older than any other open sourced proxy cache? That would make it more popular for the same reason that Apache is more popular than other open sourced webservers: name recognition? I remember that for a while, the Squid was the only proxy cache of which I knew. and the only one I had ever attempted to install.
Squid's ancestor (a caching component of the Harvest project) was the first web proxy cache, period. One of its developers (Peter Danzig) went on to NetApp and produced the NetCache, which was the first commercial proxy cache. The Open Source option predated the commercial variant by a couple of years.
There have been numerous proxy caches that have come and gone in those years, and there will likely be numerous that come and go while Squid continues doing its thing.
"That would make it more popular for the same reason that Apache is more popular than other open sourced webservers: name recognition?"
Do you really believe name recognition is the only reason Apache is the most popular web server?
It doesn't have anything to do with the huge array of capabilities that Apache has that no other web server has? Or the broad ancillary tools support? Or the huge pool of knowledge available for it? Or that it is proven reliable? Or that it can safely be expected to exist and still be a viable option in five or ten years?
But, to answer your question of whether I think Squid is popular for the same reason (or reasons, as I believe is the case) Apache is popular: Yes.
Squid is popular for exactly the same reasons Apache is popular. It is a reliable product that serves a wide variety of users very well. It is well-maintained and has a long history of being well-maintained. It is well-understood by a lot of people, so it's not going to be neglected or a source of contention if the IT guy moves to another job. It is fast enough for a lot of uses. It is extensible via a number of scriptable access points, so developers can easily make it do what they need it to do. And, despite the accusations of horrible design, it has proven itself to be quite resilient. The number of security issues in Squid, for example, has been truly miniscule in the past decade.
The funny thing is how many people are acting as though Varnish is going to somehow take the place of Squid as soon as people realize that Varnish is "better". For one small subset of problems for which Varnish is specifically built, it may make sense. But, for a huge array of other proxy and caching problems, Varnish isn't even a contender.
I should maybe explain that my first company was a web caching proxy company, building products based on Squid. I deployed Squid several thousand times over seven years. Varnish would have worked in maybe a few dozen of those deployments. Squid solves a ridiculous array of problems, even though it solves none of them as well as a purpose built application could solve any one of them. Varnish solves its handful of problems very well...and does nothing for all the rest of the use cases.
"Do you really believe name recognition is the only reason Apache is the most popular web server?"
I think that that's a huge component of it. I know that I've been in a number of shops where they deployed Apache, not because it was the best tool for the job, but because it was the only tool of which the admins knew, and they didn't know where else to look.
I no opinions about Varnish vs Squid, but I will point out that I had no idea what Varnish was until I read this article, but I've known what Squid was for a while, so they're not competing on equal terms.
