Ring slings are a length of fabric with 2 rings sewn in at one end of the cloth. The fabric is folded and threaded through the rings to form a loop, which can then be adjusted according to the size and shape of you and your baby.
Ring slings are usually worn like a sash (placed over your head and 1 shoulder). Your baby is placed between you and the fabric, with the fabric providing seat and back support. Various carries are possible including a tummy-tummy upright hold (legs in or out), a kangaroo (or facing the world) hold, and hip/back carries. Breastfeeding is achievable with a ring sling although for safety reasons caution is needed if you plan to carry your baby in a cradle (side lying) hold.
Ring slings can be used with newborns and toddlers, are instantly adjustable, and are a good carrier to share around as a 2 metre length fits most. Pick a shorter size only if you are petite and do not like excess tail fabric!
We would recommend ring slings for shorter trips from car to shop/playground etc, or for carrying your baby around the house. You should find it easy to pop your baby in and out of it while they are sleeping. It's also great for the nosy older baby who loves up and down and just loves hip carries :)