I've read that their index is powered by a custom/modified version of MySQL. They no doubt use a lot of compiled C code on the backend, and I've also heard a lot of Python.
Google has many projects and likely uses many environments. If you are referring to google.com... Google uses BigTable http://labs.google.com/papers/bigtable.html Check out this article for programming languages google uses: http://stackoverflow.com/questions/754301/what-programming-language-is-google-written-in Judging by your previous posts, I would like to recommend the site www.digg.com to you guys.
Oh hai guys, I hear this is where the most uninformed idiots of the Interwebs hang out. Room for one moar?
As a sysadmin at El Goog, search is nearly all C++, except for a bunch of internal scripts which are Python. Other systems tend to be in Java or C++. The extensions tend to not help at all, except to tell what language things were originally written in. At this point there is very little python code that is user-facing. There may be some remenants of MySQL lying around; we're moving away from them, towards Bigtable. All that said, don't think that using C++ will come up with a great website. It i in fact way harder to write a website in C++ than PHP. Google is just at such a large scale that it makes sense to optimize for server time over developer time. You most certainly are not at that point.
A number of people here suggested google uses CGI. That is not quite right. While it is true that googles uses a majority of C++ for their backend, they do not use CGI. CGI is an outdated technology that starts a process for every request that goes to the server. CGI is something connected to a common web server software such as Apache, Lighttpd, or Nginx. For the main google search; it is doubtful they use any of those. The web server itself run on the main google page is very likely a custom coded one that is not available to users outside of google. ( I am talking about the main search pages etc ) That web server likely uses a combination of technologies custom tweaked for google's use. ( such as FastCGI, WSGI, etc ) Those technologies are used to pass off HTML requests directly into C code. The database used by google, is, also, custom written for google. It is meant to be highly scalable. They have a very large number of servers across the country, all of which must be kept in sync and communicate to each other... To all saying "they use X or Y"; sure. Google is huge. You can find references saying they use anything you like. This question can only be answered for how google does some one specific thing. Even that question is hard to answer because it is constantly in flux. See the Google 'go' language. It is sort of like D, only newer. Perhaps lots of stuff is written in that? NOT. It was an experiment by a small group of users at Google. It problems runs some small parts of the company; but certainly not anything critical like the main search.
Years ago, for grins, I wrote a binary that allowed you to use QBasic as a scripting language for web. It's scary how little you can do with a 16-bit interpreter. I never understood why MS never brushed off QBasic to repurpose it as a competitor to PHP. A 64-bit QBasic with database connectivity would doubtlessly produce even more unsafe code than PHP.
Um... wow. Quick note from a long time lurker who happens to do a massive- amount of database programming and apparently is the only one who has a clue as to how the internet really functions. Perhaps I'm the only one who knows how to keep up with tech news... Yes, Google uses SQLite- however I am extremely confident it isn't used for their search. Anyone who has ever used it should know this. Even on SQlite page they state: "It is known that Google uses SQLite in their Desktop for Mac, in Google Gears, in the Android cell-phone operating system, and in the Chrome Web Browser. People are suspicious that Google uses SQLite for lots of other things that we do not know about yet. Engineers at Google have made extensive contributions to the full-text search subsystem within SQLite."- I've actually done a fair amount of work with SQLite- it definitely is wonderful for single user applications (installed on a local machine), but sucks when used as a remote database. For that no one outside of Google knows for sure but I do know they use MySQL extensively... or does no one in this forum keep up with open source news? Come on people- use your l33t google-fu and do some research before you open your mouths.. infoworld dot com/d/mobilize/mysql-get-injection-google-code-527 or Mysql's website under their list of customers...
for sure that Google use Phyton in their sites. Pyhton's founder, Guido van Rossum also working in Google dont u guys know?
I know for sure that Google uses its own compressed database system called BigTable, which they developed for their own use to handle enormous amounts of data, as well as their own filesystem called GFS (Google File System), which BigTable has been exclusively designed under. I did read about it somewhere long time ago. I believe you could easily find this information in Wikipedia for sure.