Purpose of an SSL Certificate
An SSL (Secure Socket Layer) Certificate encrypts data sent between a web page and its visitors. Without an SSL certiciate, all communications with a website are sent over plain text.
What does this really mean? It means that when you submit a form containing personal information, usernames and passwords, or credit card information and the page containing the form is not behind an SSL ceritiface, the contents of the form are visible to anyone who has access networks involved in the request. This includes anyone on your home network (if you're conecting from home), anyone at your work network (if you're connecting from work), employees of your internet provider, or emploees at the facility where the website is hosted. All of these various networks are succeptable to hackers who can listen in on form submissions and collect your personal data.
SSL Certificates encrypt the data sent to and from the web page so that others cannot access the data. If someone were to listen in on the data transmissions, the encrpted data wound not be usable by hackers.
How to Determine if a Web Page is Behind an SSL Certificate
There are usually 2 ways to determine if the web page your'e visiting is behind and SSL certificate. All modern browsers now display a small lock icon beside the address bar when the page is behind an SSL Certificate. The address bar is the field near the top of your browser window where you enter a website address to visit a website. Another way to determine if a website is behind and SSL Ceritificate is to look for https in the websites address. A web page secured by an SSL Ceriticate will include https instead of http in its address.
For reference, look at the address of this page which it https://www.linkweb.ca/ssl-certificates/. You'll also see the lock to the left of this address.
How SSL Certificates Benefit Search Engine Ranking
In August of 2014, Google announced that its search algorithm now includes SSL Certificates in determining how a web page ranks. This means that a web page behind an SSL certificate has the potential of ranking higher in organic search results over a page that is not behind an SSL Certificate.