If it's a foreign language, you learn it for use at work, travel, entertainment, but if it's a second language you're learning it for living in an English-speaking country.
Originally the Communicative Approach was a response to the Audio-Lingual Method, which consisted of dry drills that emphasised grammatical structures. It brought authentic texts in and emphasised meaning and communication rather than simply looking at grammar patterns. Nowadays, the term is used so widely that it has become a bit meaningless IMO.
- For Teachers