Overlays are a layer of hard gel or acrylic that is brushed over your natural nail to add the strength of an artificial nail to the natural nail. This prevents bending and splitting of nails and is a perfect treatment if you are endeavouring to grow your nails and add some protection to them without adding length.
Nail extensions are exactly what they say on the tin. An artificial nail tip is applied to the nail, cut to the desired length and hard gel or acrylic is applied to create an artificial nail. Ideal if you are looking to add length to your nails.