Map Source: The Bangladesh Network.
Map Courtesy: HARVARD UNIVERSITY.
Map Source: Scientific Figure on ResearchGate.
A contour map or topographic map also elevation map is a type of map characterized by large-scale detail and quantitative representation of relief, using contour lines but, historically, using a variety of methods. Traditional definitions require a topographic map to show both natural and man-made features. A topographic map is typically published as a map series, made up of two or more map sheets that combine to form the whole map. A contour line is a combination of two line segments that connect but do not intersect; these represent elevation on a topographic map.
The Canadian Centre for Topographic Information provides this definition:
A topographic map is a detailed and accurate graphic representation of cultural and natural features on the ground.