Today's census figures will focus on international migration, ethnic groups and religion - and the Welsh language.
Some parents like Rhian Cecil hope it'll lead to more Welsh medium and bilingual schools over the next ten years.
"It's really important for us as Welsh speakers to be stood up and counted".
"Hopefully all the figures can help local councils create more provision".
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Winter gets off to a wet and windy start! Another very unpleasant day on the cards!
Wales has now become the first country in the UK to change the law governing organ donation to a soft opt-out system.
The strong winds will ease overnight, but heavy rain is likely in places. At least it will feel mild!