If you have a WordPress site, you will eventually get hit with spam in the form of fake users registering, spam comments, spam coming through your contact form, and spam forum posts.
To get all of this under control, I highly recommend adding a plug-in called CleanTalk to your site. Every other plug-in that I tried let some spam squeak by, and some plug-ins actually prevented the site from operating properly. Not this one. It takes just a few minutes to set up and configure. After that you’ll have to figure out what to do with your extra time now that you aren’t moderating tons of spam comments and deleting fake users.