Sedimentary rocks are formed from sediments that have settled at the bottom of a lake, sea or ocean, and have been compressed over millions of years.
The sediment comes from eroded rocks carried there by rivers or ice, and from the skeletons of sea creatures.
Examples of sedimentary rocks include limestone and sandstone.
Limestone and sandstone
Sandstone Cliffs at Horseshoe bend, Colorado River in Arizona
Limestone cliffs surrounding Navagio Bay, Greece