>>6
I don't believe in distinguishing between kernel space applications and user space applications as such distinction holds meaning only to the professional IT expert. There's no fundamental reason why application software can't be loaded into kernel space and why many kinds of kernel software to be relocated into user space. The reason why we segregate is normally for the purpose of system administration as a kind of operating system protection.
Systems programming is indeed using within application software, but you need to consider who the target audience of the application is supposed to be. If the primary audience is for system administrators, programmers, and related experts that are going to configure and control the computer, it's probably a form of systems software. If these specific experts are not the target audience and the software's mission is to achieve any other application (e.g. download and render web pages from the network/Internet), it's probably a form of application software. Remember that these are not strictly mutually exclusive, as it's not too hard to consider the mission and target audience of the software.