An SSL creates a secure tunnel through which information including usernames, passwords, credit card numbers and more can pass safely. For websites having payment gateway we recommend SSL certification, although it is not compulsory.
Cost of HTTPS:
To obtain and implement SSL Certificate or HTTPS protocol for the website, clients have to bear an additional cost of around Rs. 5000/- annually.
Advantages of HTTPS:
A certificate guarantees the information a browser is receiving originates at the expected domain. It’s a guarantee that when a user sends sensitive data (payment information, payment gateway), it’s being sent to the right place, and not to a malicious third-party.
If data is sent in the clear, it’s possible for a third-party to sit between the server and the browser and read everything, But, even worse, if they can read it, they can change it. By hijacking a connection, a hacker can see what the browser is requesting and the site is sending; they can intercept the data sent by the site and alter it before sending it on to the browser — the user would never know.
HTTPS connections make this sort of man-in-the-middle attack much more difficult to pull off.
Google wants to send its users to secure sites and to that end has made HTTPS connections a ranking signal. That means, all else being equal — which it never is — a site with HTTPS is going to rank higher than a site without.
It’s important to note that HTTPS is a weak ranking signal. At the moment, implementing SSL is going to have a minimal impact on search positions. High-quality content is more important.
Finally, that green padlock indicates that you take security seriously and helps give users confidence.