This book contains more than 60,000 abbreviations, mainly social sciences, supplemented by science and technology, involving politics, economy, transportation, culture and education, medical care, tourism, sports, commerce, trade, insurance, communication, network, computer and many other fields. Try to include new acronyms that have emerged and become popular in recent years to reflect the characteristics of the times, such as BRT (Bus Rapid Transit), PK (player killing) duel, YOG (Youth Olympic Games), etc., and two other very Practical appendices: abbreviations commonly used on the Internet, Internet domain names of countries or regions in the world, which can meet the needs of English learners and translators.