In UiPath, the Type Into activity's Input Mode property determines how text is typed into a target UI element. The "Simulate" input mode types text using the technology of the target application, allowing it to run in the background without needing the target UI element to be in focus. It also automatically clears the field before typing, unless otherwise specified. On the other hand, the "Window Messages" input mode sends a series of Windows messages to the target application, simulating keyboard strokes. This mode supports the use of hotkeys and special key combinations, making it suitable for applications that require specific keyboard inputs to trigger actions.References:

UiPath Activities Guide - Type Into