Hello friends,
I just want to know that which language is Google Search engine built in? Please help me if someone knows. Actually I m interested in getting to know the real world implementations of C++.
Waiting for your kind replies. Thank you.

Regarding real world C++: Most of the programs on your computer are written in C/C++. It is likely that 99% of all computer games on the market are written in C++. And so on.

According to this: http://www.trap17.com/index.php/what-programming-language-google-etc_t34833.html

Google uses a lot of programming languages :)

He is right about their job requirements:

Requirements:
BS degree in computer science or related technical field, MS and PhD degrees preferred.
Experience with UNIX/Linux or Windows environments, distributed systems, machine learning, information retrieval and TCP/IP.
Extensive experience programming in C, C++, Java and/or Python.
Experience in network programming and/or developing/designing large software systems

Copied from: http://www.google.com/support/jobs/bin/answer.py?answer=75572