Ans to the Question No: 1

Classification in GIS is the process of shorting geographical data, like satellite images , into different categories based on their characteristics. it helps to understand and analyses things like land cover type, urban areas , or natural feature on maps. 

Ans to the Question No: 2

Supervised classification in GIS a method where the computer algorithm learns from example data with known categories. it uses training  data to classify new data automatically info predefined classes or categories.