K:

kernel: The core of the operating system - manages memory, loads processes and libraries, schedules threads for execution. Symbian OS's Kernel is called EKERN.EXE.
key: A value constructed from one or more columns in a row, which can be used to identify the row within an index.; See also: column row index
key event: An event from the window server indicating a key down, repeat or up.; See also: window server pointer event
keyboard focus: Any particular key event is sent only to one window group. This is the group that has current keyboard focus.; See also: window group
keyboard repeat rate: The time interval between repeated key events generated by the window server. There are two settings involved: the initial delay before the first repeat event is generated, and the interval between subsequent events.; See also: auto-repeat