The tactile feel of the keys influences the way we type, and again is a personal preference.
Traditional ‘mechanical-switch’ keys are still available. These type of keys are what the earlier keyboards used and require a larger movement of key depression.
More modern keyboards are slimmer and keys have a lower profile. This was born from the keyboards originally made for laptop/notebook type computers. They use less key depression.
Shown: Smartfish Technologies Pro:Motion