An SSL/TLS certificate is a digital certificate that authenticates the identity of a website and enables an encrypted connection between the web server and the user's browser. This encryption helps protect sensitive information, such as passwords and credit card numbers, from being intercepted by malicious actors during online transactions. When a user visits a secure website, the SSL/TLS certificate ensures that the data exchanged remains private and secure. Websites with these certificates display a padlock icon in the address bar, indicating that the connection is safe. This is essential for building trust with users and ensuring data integrity online.