A new law has come into effect in Wales outlawing any form of corporal punishment of children, including smacking, slapping and shaking.
The change means that, as is already the case in Scotland, hitting a child will be considered common assault the same as for adults.
Smacking a child was previously considered unlawful but allowed as long as it constituted "reasonable punishment".
This remains the case for the law in Northern Ireland and England.
What was considered "reasonable" depended on elements including what mark was left on the child and whether a fist or other implement was used.
More than 60 countries around the world have laws against the physical punishment of children.
The United Nations Convention on the Rights of the Child says that children should be protected from physical and mental harm.