WordPress is one of the most popular Content Management Systems (CMS) in the world. It is because of its popularity that it is continually targeted by malicious hackers and spammers who seek to identify insecure websites and use these insecurities to their advantage.
Spammers generally want you to look at them and click on their links. Spam can from a number of different sources. Email spamming, blog comment spamming and online forum spamming are the most popular/common.
Spamming is performed automatically by way of scripts. The spammer doesn’t actually sit down and type spam comments or send spam emails manually. Comment spamming is simply posting unwanted comments to blog posts. Most of the time, they do this as a way of advertisement to get you or your readers to click and go to their site which maybe filled with income producing advertisements or more lucrative is including their URL’s into the comments so they get highly sought-after backlink. By the spammer putting links to their site/s on your site, they are increasing their SEO score with Google – as google sees all these other sites pointing to theirs and so thinks, that their site is relevant and pushes it up the SEO tree.
It is a good idea to do what you can to eliminate comment spam as much as possible. Leaving the spam on your comments will just lower your online reputation, and lower your potential audience.
An easy way to deal with spam on your WordPress site is to manually delete them, however it is much simpler to have a plugin do this for you. Search the WordPress plugin library for ‘Spam’ and select one that is suitable.