An SSL certificate can be used to encrypt data. I see a lot of websites that use an SSL certificate, even though they don't need to encrypt data since no confidential data is sent.
Why do they do this? Some websites use SSL certificates only to get the trust of a visitor. SSL certificates which will show a green address bar or so are more expensive.
I saw this thread: Does SSL on a company's website make the company appear more credible? but I'm not necessarily talking about a company.
But does it really improve the user experience?