A half and last year educated us that WordPress security shouldn't be taken lightly by any means. Between 15% and 20% of the world's high traffic sites are powered by WordPress. The fact it is an Open Source platform and everyone has access to its Source Code makes it a tempting prey for hackers.
I back up my blogs frequently using a plugin WP DB Backup. If anything happens I will always restore my blog to the last settings. I use WP Security Scan free plugin to scan my site regularly and WordPress Firewall to block suspicious-looking requests to fix hacked wordpress site.
I protect an access to important files on the blog's server by placing an index.html file in the particular directory, which hides the files from public view.
Yes, you want to do regular backups of your site. I recommend at least a weekly database backup and a monthly "full" backup. More. If you make additions and changes to your website, definitely more. If you have a community of people which her explanation are in there all the time, or make changes multiple times a day, a link daily backup should be a minimum.
You could even get an SSL Encyption Security for your WordPress blogs. The SSL Security makes encrypted and secure communications with your blog. So that all transactions are recorded, you may also keep history of communication and the all of the cookies. Make sure that all your blogs get SSL security for protection.
Change your password, try here often, or at least your WordPress password and admin username and collect and utilize good WordPress safety tips to keep hackers out!