A water purifier is a device that removes impurities from water in order to make it safe to drink. Water purifiers can use a variety of technologies to remove contaminants, such as reverse osmosis, carbon filtration, and UV light. Water purifiers are used in homes, offices, and other locations to provide clean, safe drinking water, especially in areas where the quality of the tap water may not be reliable or may be contaminated with impurities such as bacteria, viruses, and chemicals. Water purifiers can help to reduce the risk of waterborne illness and improve the taste and quality of the water that we drink.

There are many different types of water filters available for use in the home, and the best option for you will depend on your specific needs and budget. 

Some of the most popular types of water filters include:

Reverse osmosis systems: These systems use a membrane to filter out impurities from water, and are effective at removing a wide range of contaminants, including bacteria, viruses, and dissolved solids.

Carbon filters: These filters use activated carbon to remove impurities from water, and are effective at removing chlorine, bad tastes and odors, and some chemicals.

UV water purifiers: These systems use UV light to kill bacteria and viruses, and are effective at eliminating microorganisms that can cause waterborne illness.

Pitcher filters: These are small, portable filters that you can use to filter your drinking water. They are generally affordable and easy to use, but they may not be as effective at removing contaminants as other types of filters.

Here are 10 popular water purifiers that are available in India:

1. Kent Grand Plus
2. Aquaguard Enhance RO+UV+UF
3. Livpure Glo 7-Litre RO + UV + Mineralizer
4. Eureka Forbes Aquasure from Aquaguard AMRIT 20-Litre Water Purifier
5. Tata Swatch RO+UV Water Purifier
6. Havells Max Alkaline RO + UV + Mineralizer
7. Pureit Copper+ RO+UV+MF Water Purifier
8. Aquatec Plus RO+UV+UF+TDS Control
9. AquaSure Deluxe RO+UV Water Purifier
10. Blue Star Aristo RO+UV+UF+MAT Water Purifier

Some factors to consider when choosing a water purifier may include 

- the type of filtration technology used, 

- the cost of the unit and any replacement filters or cartridges, the size and capacity of the unit, 

- the specific contaminants that the purifier is designed to remove. 

- It may also be helpful to read product reviews and consult with a water treatment professional to get a better understanding of the performance and effectiveness of different water purifiers.

- You may also want to consider consulting with a water treatment professional to determine the best option for your specific needs.