Cognitive load in UX refers to the amount of mental energy users need to understand and use an interface. The less brainpower a UI requires from users, the faster they will complete their tasks. This, in turn, results in a more pleasant user experience.

It's not possible to eliminate cognitive load entirely. After all, people use apps and websites to find new information about your product, organization, or content. This is called intrinsic cognitive load — the effort of absorbing that new information and of keeping track of their own goals.

UX writers should strive to minimize extraneous cognitive load — the processing that takes up mental resources but doesn't help users understand the content.^[1] Consistent writing is one of the best ways to do that.