With SSL installed on your hosting account, your website can be accessed by both secure (httpS) and non-secure (http) connections. The secure connection is a bit slower than the non-secure one because the data transfer has to be encrypted on both ends.
That's why secure connection should be applied primarily to pages that contain sensitive information, such as pages where people enter personal details, billing information, etc. We advise you to setup secure connection only for such pages - the rest of your website will load much faster with the non-secure connection.