Political maps of India have changed dramatically over the years. Boundaries of States have changed, names of States have changed, and the number of States has changed. When India became independent, we had a number of provinces that the British government had organised only for administrative convenience.
Then a number of princely states merged with the newly independent Indian union. These were joined to the existing provinces. This is what you see in the first map. Since then boundaries of States have been reorganised many times.
During this entire period, not only did boundaries of States change, but in some cases, even their names changed according to the wishes of the people of those States. Thus, Mysore changed to Karnataka and Madras became Tamil Nadu.