Introduction to the leaflet Part 1

If you wonder how to start in the leaflet than this video for you.
Leaflet is the leading open-source JavaScript library for mobile-friendly interactive maps. Weighing just about 39 KB of JS, it has all the mapping features most developers ever need.

Leaflet is designed with simplicity, performance and usability in mind. It works efficiently across all major desktop and mobile platforms, can be extended with lots of plugins, has a beautiful, easy to use and well-documented API and a simple, readable source code that is a joy to contribute to.
If you are interested in the downloading the dem data from Qgis
How we can visualize the COVID 19 patient using web maps.
How to find the UTM zone of your data which is in Geographic coordinate system in ArcGIS
How to make the raster image of the Higher Resolution from low resolution(30 M Landsat to 15 M )
Downloading the Landsat data of the specific bands and of required area of interest.
Calculating the Area of the Raster data in ArcGIS