From twinkling constellations to stellar life cycles, this starry skywatching quiz will test your cosmic knowledge.

An optical illusion is a visual phenomenon where our eyes perceive something differently from reality, tricking the brain ...

Backed by years of research in cognitive psychology, the Blue Dolphin Rule will help you replace harmful thoughts with helpful ones.

Countries with the Highest Average IQs in 2025 The latest data from the International IQ Test as of January 2025 reveals intriguing trends in cognitive ...

Paul Soucy has led the Credit Cards content team at NerdWallet since 2015 and the Travel Rewards team since 2023. He was an editor with USA Today, The Des Moines Register and the Meredith/Better Homes ...