Conversion rate is how many people out of every 100 who visit a website actually do something, like buying stuff or signing up for emails.
For instance, if 100 people check out a website and 10 of them buy something, the conversion rate is 10%.
Making conversion rates better is a big deal in online marketing.
It means getting more people to do what you want them to do on your website, like buying stuff or signing up for things. This helps businesses get more out of their online efforts and make more money.