Q. What's the common thing between C# and Javascript?

A. They are almost available every where:

- you can do front-end web programming in JavaScript (no doubt), and back-end web programming in Javascript too (Node.js)

- you can do desktop programming in C# on windows/linux/mac. (thru mono)

- you can do mobile programming in C# on windows mobile/iOS/Android (thru monotouch/monodroid)

- you can do game programming in C# on xbox360/window mobile/iOS/Android, and even PS Vita!! (overlapping sound: nani?!) Actually, see this for more details.

And on the latest windows 8, you could create apps in JavaScript or C#. (singing "whatever you like")

Time to study JavaScript...