I have a door but no house, keys but no lock, and I show you things but I'm not a window. What am I?

This clever riddle plays on the many metaphorical aspects of a common device that has become indispensable in our daily lives. When we consider the "door but no house," this refers to the digital "doors" or "ports" within a computer's operating system and network (Review) architecture. These are pathways that allow data to flow in and out, rather than physical entrances to a building.

Similarly, the "keys but no lock" points directly to the keyboard, an essential input device. Each key on a keyboard doesn't open a physical lock but rather serves to input characters, commands, and functions, unlocking a world of digital possibilities on the screen. The absence of a traditional lock emphasizes the non-physical nature of computer security, which relies on passwords and encryption instead.

Finally, "I show you things but I'm not a window" perfectly describes the computer monitor or screen. This display actively presents visual information, from documents and images to videos and complex applications, allowing us to interact with the digital world. While it provides a view into digital content, it is distinct from a transparent pane of glass that you might look through in a building. This riddle beautifully encapsulates the multifaceted nature of a computer, highlighting its blend of tangible components and abstract functionalities.