Internet and computer basics

TLS

A set of rules (a protocol) that protects information sent over the internet. It turns the information into a jumble that only the other end can turn back (encryption), so nobody along the way can read or change it, and it uses a digital certificate to check that the other end really is the server for that address. Websites use it through HTTPS, and email and many apps use it too. Its predecessor SSL is outdated and no longer used, but people still often say SSL when they mean TLS, as in "SSL certificate". It only protects information on the way; it does not show that whoever runs the other end can be trusted.