What is an SSL certificate?
An SSL certificate provides security for online communications. When you visit a website that has been secured with an SSL certificate any data that gets sent to and from the server is encrypted.
This is similar to sealing a letter in an envelope before sending it, it prevents the postman from being able to eavesdrop and read your message.
When your site is secured with an SSL certificate you will be able to visit it using 'https' instead of the regular 'http'.
Do I need an SSL certificate?
Any website that records client or visitor details would benefit from the additional security. You can ensure your clients that their data is safe and every pre-caution is being taken to protect their personal details.
This is especially true for e-commerce sites where credit card or other sensitive data is being entered.