Let’s Encrypt allows anyone to get a free SSL certificate with ease. There are others such as StartSSL (which is great as well) but none are as simple and easy to use as Let’s Encrypt.
git clone https://github.com/letsencrypt/letsencrypt cd letsencrypt ./letsencrypt-auto --agree-dev-preview --server https://acme-v01.api.letsencrypt.org/directory certonly
Follow the on screen instructions and then configure your web server for the new SSL certificate. Certificates are stored in