Knowing English increases your chances of getting a good job in a multinational company within your home country or for finding work abroad. It's also the language of international communication, the media and the internet, so learning English is important for socialising and entertainment as well as work!
i think personally english is so popular because english is the most spoken language in the world and more than a quarter part of it speakthe language. Many people use this language for trading or for business and most movies produced in the world are mostly english and because its the 2nd language schools teach children because its useful to have as a language and it helps get oppertunities in the world like a job for example. So english is so popular because most movies are published in english and because its useful in everyday life so learning English is important for socialising.
