For general-purpose computing it's probably C++. A lot of software now goes into websites, which means that ruby, php, perl, java, javascript are also widely used.
Ruby on Rails is becoming popular day by day though yet it is not as popular as Java but it has quite good growth in future
The languages in the first cluster, Java, C, Python, and C++, are pretty much universal languages. They're not tied to a specific programming platform or focus. The most interesting clue is the second cluster, containing JavaScript, C#, PHP, and Swift. JavaScript and PHP are mainly web development languages. If you need to learn programming languages, then must visit Best & Affordable Computer Science Homework Help