A contour line is that line that on a map joins all the points that have equal conditions and altitude. Contour lines are usually printed on maps in sienna for terrain and blue for glaciers and the deep sea.
These contour lines are an important way to show the rise and fall of the land on a map. Contour lines show all places that are at the same height above sea level. They also tell us about the slope of the land. On a steep slope, the lines are close together.
Contour lines are the most distinctive feature of a topographic map. Contour lines are lines drawn on a map that connect points of equal elevation, which means that if you physically followed a contour line, the elevation would remain constant. Contour lines show the elevation and shape of the terrain.
Google Earth Engine is a platform for scientific analysis and visualization of geospatial data sets, for academic, non-profit, commercial and government users. Earth Engine hosts satellite images and stores them in a public data archive that includes historical images of the Earth dating back more than forty years. The Google Earth Engine API provides a library of functions that can generate level lines from the global digital models available from the ALOS and STRM projects.
Here you will find the complete code: link