Let’s Encrypt is a free certificate authority that can be used to create HTTPS websites. This project is managed by the non-profit Internet Security Research Group (ISRG). Let’s Encrypt works well for low and medium traffic websites. Websites that experience a great deal of web traffic or need warranty coverage should consider a paid certificate authority. Let’s Encrypt certificates also expire every 90 days.
Certbot is a free tool made by the Electronic Frontier Foundation (EFF) in order to automatically use Let’s Encrypt certificates on manually-administrated websites to enable HTTPS.
More information is available at: