Trying to understand web services

[Dwayne Barsotta]

I just read a Quora post about LinkedIn moving from Scala.  One poster mentioned they use a list of languages like Java, python, C++, C# and more. I understand using HTML,CDs, js and php all together.  Why would an organization also use such a large stay off back office languages to provide one site?  

Using all these languages, one language would need to be a "controller" of sorts. The middle man?  What language works better with all the others?

I have seen/read about losing c language libraries files in Java, but the complexity of so many languages seems, I don't want to say a waste but couldn't all the services be supplied with one of two languages easier?

[Tim Moores]

Even a single web site might use multiple languages, like PHP for the front end and Java for the back end. And just about any company will have back office systems and many background jobs for various tasks which need not be written in those same languages, as there they may not interact with one another at the code level at all. It may also be that they bought other companies that had their systems written in different languages.

[Tapas Chand]

Dwayne Barsotta wrote:...Why would an organization also use such a large stay off back office languages to provide one site?

To the user it may seem as a single site, but inside there may be thousand of modules.
If a module is already developed and working well in some language, it is beneficial to integrate that (of course after analysis) instead of creating that module from scratch in another language.