WhatsApp is a messaging and voice-over-IP service that was founded in 2009 by Brian Acton and Jan Koum. It was acquired by Facebook in 2014 and currently has over 2 billion monthly active users worldwide. The app offers a range of features including text and voice messaging, voice and video calls, file sharing, and group chats. It also uses end-to-end encryption to protect user data and ensure privacy.

WhatsApp is available on multiple platforms including iOS, Android, Windows Phone, and the web. It also offers a separate app called WhatsApp Business for small businesses, and in 2021, it introduced in-app shopping options. However, the app faced criticism for its updated privacy policy in early 2021, which allowed Facebook to access user data for advertising purposes. This led to a migration of users to other messaging apps such as Signal and Telegram.

Despite the privacy concerns, WhatsApp remains one of the most popular messaging apps in the world. It is particularly popular in countries such as India, Brazil, and Mexico. WhatsApp has revolutionized the way people communicate by providing a simple and easy-to-use platform for exchanging messages and making calls. It has also enabled businesses to communicate with their customers in a more efficient and effective way. Overall, WhatsApp has become an integral part of modern communication, and its continued popularity is a testament to its usefulness and convenience.