We highly recommend using rug pad to prevent from slippery. If the rug is being used on  the wooden floor or granite or marble, it is must important. You can find different types of rug pads in the market.

Few of them you may like on Amazon are:
8' X 10' ENDURANCE 32® 100-Percent Recycled Felt Rug Pad

Mohawk Home Dual Surface Rug Pad, 8’x10′, Multi

Non Slip Area Rug Pad Size 2' X 8' Extra Strong Grip Thick Padding And High Quality

Eco Plush TM 1/2" Felt Rug Pad by Rug Pad USA, Preserve & Protect, Cushioned Rug Padding SAFE FOR ALL FLOORS - 20 YEAR WARRANTY (9x9)

Every rug pad varies depending on your rug type. Larger rugs may only require a Cushion rug pad whereas smaller area and runner rugs may need a good grip to prevent from slipper or accidents.