The percentage of the people who clicked through to your website who then took a positive action, such as purchasing something or signing up for a newsletter.
Conversions means in Google Analytics: achieving goals. A goal can be set up in Analytics in the form of an ordered product, a newsletter subscription or a page sent via a tweet.
Conversions are expressed in conversion rates. A conversion rate indicates how many percent of visitors who have completed specific conversion. For example, if there are 100 visitors on your website but 20 visitors is going to buy your product, than the conversion rate will be : (20/100)*100% = 20%. For a better analysis it’s important to know your conversion rate.
This conversion rate can relate to all site visitors, but also be segmented. This allows you to view the conversion rate per traffic source.
As well as the search ability of a site can be optimized, it is also possible to optimize the conversion. The fewer obstacles in the way to a goal, the more people will complete that goal.