It's not every day that Google mentions a way to rank higher but they just did. If your website uses SSL certificates (https / security), Google will rank your website a little bit higher. They're actually telling everyone this:
HTTPS as a ranking signal (googlewebmastercentral.blogspot.com)
For these reasons, over the past few months we’ve been running tests taking into account whether sites use secure, encrypted connections as a signal in our search ranking algorithms. We've seen positive results, so we're starting to use HTTPS as a ranking signal. For now it's only a very lightweight signal — affecting fewer than 1% of global queries, and carrying less weight than other signals such as high-quality content — while we give webmasters time to switch to HTTPS. But over time, we may decide to strengthen it, because we’d like to encourage all website owners to switch from HTTP to HTTPS to keep everyone safe on the web.
The main reasoning, as the article explains, is that they want websites to be secure and encrypted for the overall security of the Web, so by ranking those websites higher, Google is encouraging website owners to use SSL.
If you host your own shopping cart, then your website should already be using SSL for the cart checkout. To know if you're using SSL, you'll see the web address in the browser change from http to https.
Contact your website host about getting an SSL certificate set up for your website. Every SSL certificate does require a dedicated IP address, so you will most likely also have to pay for that. The reason is technical but it's that you can only bind one port 443 to an IP address. With shared hosting, you can have multiple websites sharing the default website hosting port (port 80) but there can only be one SSL certificate per IP address - they all can't share it... well, they can but it won't match the domain and it'll throw ugly errors to website visitors.
Even if your website doesn't have shopping/e-commerce or have forms that ask for sensitive information, you should still consider adding SSL to your website.
Don't expect miracles with this website upgrade. Don't expect to move up 30, 20 or even 10 positions. How much higher you will rank by adding SSL will depend on factors like how much competition you have and so forth. For good SEO and high rankings, that (of course) depends on many factors. This happens to be one of them and it's one that Google's actually announcing, which is rare. You'd kind of have to be dumb to not take advantage of it. 🙂
With that said, what's kind of funny is how the SEO industry is reacting to this announcement - of course, they kind of see Google as a necessary evil. 🙂