Google Algorithm updates impact your website rankings by moving your rankings lower if you are not doing what Google wants. If, however, you are following Google's direction for how to provide web users with a better experience, Google will improve your web pages rankings in search results. (Google's most recent update was the Mobile update, continue reading to learn more). Higher rankings means more traffic and if it is the right kind of traffic this should lead to higher sales and profits. There is a large list of factors that affect search engine rankings and this list is always changing as google makes more algorithm updates. Currently, it appears the greatest factor that impacts rankings is the click through rates of your pages. In this article, you can find and overview of all of the key factors currently used by Google to determine rankings.
On this page there is also a podcast that discusses what is Google's search algorithm, what factors are currently included in the algorithm, what factors currently carry the most weight and what updates Google has made is the past to the algorithm they use to determine search result rankings. If Google's search algorithm means nothing to you, this podcast is a great place to start.