At the time of writing this article, there were more than 80,000 plugins available, some in the free WordPress plugins directory, and others from 3rd party sites. Not all of them are great, which leads to the question that which WordPress plugins should you install on your website?
My recommendation is to install the minimum number of plugins needed to accomplish what you want to do with your website. Look for plugins with lots of 4 and 5 start reviews, and lots of downloads. For specific plugin recommendations, please visit the resources section of WebStores University and this page.
In addition to the WordPress repository, here are a few other places to look for quality plugins: