Each paradigm has many individual experiments within it, a majority of which are created by other users. The verified experiments are at the top of each page and have black bars at the bottom of their respective experiment cards.
If you'd like, you have the ability to create your own experiment and you can recruit participants through the link for your experiment (once it's published, of course). If you find an experiment that you really like, then you can also copy and edit it to make it your own.
Additionally, you have the ability to download your individual results from any experiment that you participate in, as well as the ability to collect data for any experiment that you create or copy given that you have an account.