|natural = hill|
|A less prominent peak|
|Used on these elements|
|Status: in use|
|Tools for this tag|
A hill is a piece of land that rises higher than everything surrounding it, like a peak.
Simply put, not all mountain summits are peaks. The less prominent ones are hills.
Compared to a natural=peak, a natural=hill a is less prominent, but like a natural=peak, a hill has an obvious summit and might be a part of a series of summits. The highest in the range of summits would be a natural=peak, and the lower, less prominent ones might be natural=hills.
One used differentiator is the height (ele=*), but this is probably not be a good way to separate them. The same goes for the steepness of the hill, the geological formation method and vegetation.
A clear way to separate hills from peaks is Topographic prominence. How prominent one peak is from the next. The Wikipedia page prominence Topographic_prominence has a detailed explanation of how hills and peaks are classified by using topographic prominence.
Using this method it is possible to separate the two.