Many languages have a few "killer" features/libs/uses. I often start with a project that uses one of them. Eg: ruby => rails python => nltk,django,opencv,

Many languages have a few "killer" features/libs/uses. I often start with a project that uses one of them. Eg: ruby => rails python => nltk,django,opencv,scipy c++ => opengl,opencv java => opencv js => node,angular,ember clojure => overtone That way you learn the language and some specific good use cases of it.