WATCH: How do you know if you're colour blind?
While colour blindness presents itself in various different ways, all types of the condition are defined by one thing - a mixing of some colours, and a complete inability to perceive others.
It's all caused by optic abnormalities within your eye, which mean that your brain process light differently.
You can be born with colour blindness, or it can develop over time - but it's typically very difficult to diagnose.
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