Software is generally divided into system software, which manages the computer's internal hardware and resources (such as the operating system), and application software, which is installed to let the user perform a specific task, such as browsing the internet, writing documents, or editing photos.
Firefox is a web browser: a program a user opens to visit websites and interact with the internet. Since browsing the web is a specific task performed by the user rather than a background function that manages computer hardware, Firefox falls into the category of application software.
It is not system software, because it does not manage hardware resources or provide the platform on which other programs run; the operating system does that. "Application package" and "computer tools" are not the standard classification terms used to distinguish types of software in this context.
Examination reminder: classify any program by asking whether it manages the computer itself (system software) or helps the user perform a specific task (application software); a browser always falls into the second category.
