A balance bike is a small bike for toddlers. It has no pedals and rather fat pneumatic tyres. Most bikes come with one brake, although most toddlers will slow down using their feet at first.
If your child is a bit bigger, you can just remove the pedals on a bike and transform it into a balance bike.
This is a step-by-step guide to teaching your toddler to cycle on a balance bike from CTC, the national cycling charity in the UK.