An interaction technique, user interface technique or input technique is a combination of hardware and software elements that provides a way for computer users to accomplish a single task. For example, one can go back to the previously visited page on a Web browser by either clicking a button, pressing a key, performing a mouse gesture or uttering a speech command. It is a widely used term in human-computer interaction. In particular, the term "new interaction technique" is frequently used to introduce a novel user interface design idea.

Although there is no general agreement on the exact meaning of the term "interaction technique", the most popular definition is from the computer graphics literature:

An interaction technique is a way of using a physical input/output device to perform a generic task in a human-computer dialogue.

A more recent variation is:

An interaction technique is the fusion of input and output, consisting of all software and hardware elements, that provides a way for the user to accomplish a task.

From the computer's perspective, an interaction technique involves:

Consider for example the process of deleting a file using a contextual menu. This assumes the existence of a mouse (input device), a screen (output device), and a piece of code that paints a menu and updates its selection (user feedback) and sends a command to the file system when the user clicks on the "delete" item (interpretation). User feedback can be further used to confirm that the command has been invoked.

From the user's perspective, an interaction technique is a way to perform a single computing task and can be informally expressed with user instructions or usage scenarios. For example, "to delete a file, right-click on the file you want to delete, then click on the delete item".