There are millions of blogs. Money is being made by some people and some do not. Most of the bloggers use WordPress at the moment. You need to make certain that your blog is secure.
By default, the newest version of WordPress is pretty darn secure. The development team of WordPress has considered anything that might have been added to some secure your wordpress website plugins. Before, WordPress did have holes but now most of them are stuffed up.
Backup plug-ins is also important. You want to backup database and all the files you can bring your blog back like nothing.
You should also place the"Anyone Can Register" in Settings/General to away, and you should have pop over here some sort of spam plugin. Akismet is the one I use, the old standby, but there are lots of them these days.
Another step to take to make WordPress secure is to upgrade WordPress. The reason behind this is that with every upgrade there come fixes for security holes that are older which makes it essential to upgrade.
Do not use wp_. Web hosting providers are eliminating that default but if yours doesn't, adjust wp_ to anything else but that.