Information systems software refers to the code that makes the computer work. Hardware without software lacks the ability to do anything useful. Hardware and software must work in concert to create functionality.
Information system software comes in two primary types: system software and application software. The system software is what most of us call the operating system; it enables the system to run at its basic level. The application software is the type with which most users will spend their time interacting. This type of software includes functional websites, servers, and networks, which are always at risk of security breach.
Threats can be internal or external; the point is that a web server and site host present serious risks for security. This is because, by design, servers are an open window to traffic. Systems software needs specific security measures, regular maintenance, and updates in order to maintain a basic level of security. It is critical to note that risks can never completely be eliminated. They can only be mitigated.