Record
Activate the corresponding mode that you want to animate, change the parameter and press the Record (or via Autokeying). These settings are available for every object in the Coord. Tab, where keys can be set as well.
When animating changes in scaling, make sure that you use the Object
This mode is only for use with polygonal objects. The position of all object points will be recorded. See also here.
In this mode, in conjunction with Key Selections, only the selected parameters will be applied when recording keyframes. This works both in the Autokeying
Record Active Objects
This does not apply to Position, Scale and Rotation settings!
If this option is deactivated in Autokeying mode, only the vector keys (position, size, rotation, color) that have actually changed will be recorded, i.e., if an object only moves in the Z-direction a key for only the Z-direction will be recorded.
Activating this option will record a key for all three vectors, regardless of whether or not an object changes with regard to a given vector.