Do I need SSL?

The most sensitive data I'm submitting is name, email, and phone number.  Is this something that should have SSL?  Why is there a cost for SSL?  If the URL https is what indicates you are using SSL, then google forms have https on their link for the forms you create.  I'm just wondering.  Thanks.

SSL (Secure Sockets Layer) is a standard technology behind establishing an encrypted connection between a web server (host) and a web browser (client). The data shall be transmitted securely when SSL is used with your website. It is recommended to use SSL if you are transmitting sensitive information through your website such as customer information or Credit card information, etc. Using SSL on your website enables your customers to trust your website that their information is transmitted securely. You can learn about SSL more at this webpage.

It is not just SSL when we talk about data security, there is something more to provide security against malicious attacks, etc to protect. The information provided in the thread here could help you in understanding much more about the data security that we take care of.

Hope this information helps!