Resident is a permanently running application to protect your system. Currently, it consists of a browser helper for Internet Explorer that will block download of files known as malicious (spyware installers for example).
This page inside Spybot-S&D allows you to install/uninstall this helper as well as view the report of which pages it has blocked (that should only appear if the first layer of protection, the main IE immunity, did not stop the culprit).

The second resident tool is the TeaTimer

You can find the resident tools in the tools section.