In the world, there are many deferent languages that people used for communication with another people in their countries like: English, Chinese, French, Japanese...But English is a language that has popularity and more important than any other languages.
The statistics answer the question. About four hundred million people speak English as a first language and another three hundred million use English as a second language. It is the official or semi-official language in a lot of countries and of many international organizations.
For example the International Olympic Committee always holds meeting in English. Air Traffic control and communication at sea around the world is always in English. About seventy five percent of all the letters and texts are in English and eighty percent of all the information in the world's computer is in English.
By the way it is easy for searching blog or website through Search Engine. Because the internet users always use English language for searching.