What is the bounce rate and how can you reduce it?
The bounce rate is a marketing metric that allows you to judge the quality of your traffic. It's the percentage of visitors who visit only one page and then leave. For example, if you have 100 visitors on your website and 20 of them visit just one page and leave while the rest visit at least 2 pages, your bounce rate will be 20%.
It could be interesting to check it depending on the source of your traffic. If the bounce rate a partner provides is high, maybe you should cancel this partnership? On the other hand, if the bounce rate for a specific keyword for visits from Google is really low, maybe you should focus on this keyword!
What is a good bounce rate?

Content Website
The goal of a content website is to provide the answer to a visitor, and then to have them click on an ad. A bounce rate of 60% is still pretty OK.

eCommerce Website
Visitors on ecommerce websites should visit many pages before buying a product. The lower the bounce rate, the better. One of less than 20% is pretty good.

Local shop
People looking for a local shop are looking for what the shop does (so they will visit many pages), or just a phone number or menu. A bounce rate of 40% is acceptable.