Too Long; Didn't Read
There are thousands of programming languages in the world, only about 20 of them are widely used in IT industry. Programming languages are designed for the purpose: express your ideas. With computer used more widely, more problem domains need involving computers, different programming language are invented for specific different domains. The true reason why we can master all programming languages is: There are limited number of languages concepts, let’s say less than 15 which commonly used. Programming language is a tool for expressing, it contains two side:Express your ideas with other programmers, so other people can understand your code, and maintain code base with you.