SSL certificates are used to encrypt sensitive personal information, like on ecommerce websites where a customer can enter their credit card details. This is important as the information a user sends on the internet is passed from computer to computer to get to the destination server. Any computer in between the user and the destination server can see this information. Encryption ensures that the data is useless to anyone intercepting those details. This data cannot be modified or corrupted during transfer, intentionally or otherwise, without being detected.
Users can tell if they are connected to a website that has a valid SSL certificate if the URL begins with https:// instead of http://. Some browsers will make it easier for you to check that the website you’re visiting is using a secure connection by highlighting it with a padlock icon in the address bar, as seen below:
And, it’s not just security that benefits from having an SSL certificate. Google announced that by switching to HTTPS it will give your website a ranking boost on search engine result pages, albeit only a minor one. The search engine giant has previously said that it may increase the strength of using HTTPS as a positive ranking signal in the future. So, it may be time to switch your site if you're not already using HTTPS via SSL.
Ordering an SSL certificate is simple, and is something that your hosting provider should be able to assist with.