1. Usage

Membership was initially limited to Harvard students, gradually expanding to other North American Universities. Since 2006, Facebook has allowed everyone to register from 13 years old, except in the case of a handful of nations, where the age limit is 14 years.

Facebook can be accessed from devices with internet connectivity, such as personal computers, tablets, and smartphones. After registering, users can create a profile revealing personal information about themselves. They can post text, photos, and multimedia which are shared with any other users who have agreed to be their friend or, with different privacy settings, publicly.

Users can also communicate directly with each other with Messenger, join common-interest groups, and receive notifications on the activities of their Facebook friends and the pages they follow.

2. Controversies

The subject of numerous controversies, Facebook has often been criticized over issues such as user privacy (as with the Cambridge Analytica Data Scandal), political manipulation (as with the 2016 US Elections), and mass surveillance.

Facebook has also been criticized over psychological effects such as addiction and low self-esteem, and various controversies over content such as fake news, conspiracy theories, copyright infringement, and hate speech. Commentators have accused Facebook of willingly facilitating the spread of such content, as well as exaggerating its number of users to appeal to advertisers.