What is a Catchment Area and Watershed? Any difference?

Catchment Area:
Catchment areas are locations in low lying regions in which water from higher areas collect into a single water body. The sources of water collected can vary from rainwater to melted snow. Catchment areas may drain their water into other lower lying basins or into a single place, usually a lake, in the case of a closed catchment.
 
 
Watershed:
The land area that drains runoff (rain or snow) into a lake, river, or a stream is called watershed.
It is an area covered by a system of surface and subsurface water flowing into a common terminus, indicates a geohydrological unit comprising of all land and water within the confine of a drainage divide. It refers ridge to valley approach to demarcate a watershed

(How to find a catchment area using Software will be explained in ARC GIS playlist)
Part 1 Link:    • Calculating/Delineating Catchment Are...  
Part 2 Link:    • Calculating/Delineating Catchment Are...  
Part 3 Link:    • Calculating/Delineating Catchment Are...  
Part 4 Link:    • Calculating/Delineating Catchment Are...  
Arc GIS PLAYLIST LINK:    • Arc GIS