Samsung M series: (concentrated in Indian market)
Battery centric portfolio. M series phones always have a large mah of battery. It's mainly concentrate in Indian market. M series have worse software and app support. But definitely good with old chipset and massive battery.
Samsung A series: (formerly J series)
This series usually comes with a budget phone with good flagship like features. Mainly for European market. A series get good app support and software support. (Be frank, don't compare with other manufactures with updates it will always delay)
Samsung S series:
It's only for flagship phones. It has better resolution camera, quality Eos and iOS stabilization, always have IP rating for dust and water etc. But due to the high efficiency chipsets those battery backup is really worse. In A series the chipsets will be 8 to 11 nanometer so it's energy efficient. Oh sorry I forget one thing S series are too costly and it's only aimed people with financially sound 😂
