“WordPress is a free and open-source tool and a content management system (CMS) based on PHP and MySQL.” –Wikipedia July, 2015.
WordPress uses a plugin architecture and a template system we call “Themes.” The plugins along with the themes are being developed and updated daily from all around the world. This is a very dynamic development (coding) process and sometimes creates vulnerabilities (holes that can be exploited). These holes allow malicious code additions and other hacking activities to take place within your website. Since our websites are under attack every day from many different places around the world, we need to be vigilant about closing any of these holes as quickly as we can.
To help you stay slim, you can review your site’s load time at Pingdom. If you have image sliders on any of your web pages, keep in mind that all those images you load into the slider have to download ahead of the slider animation. Your total slider load should be under 800 KB. This would be the same for any animation, including FLASH or interactive location maps with layers.