Use sentence-style capitalization

In sentence-style capitalization, you capitalize only the first word of a sentence or phrase and proper nouns.
Example
This sentence and the subhead of this section both use sentence-style capitalization.

Although all-uppercase text is used occasionally on webpages, in advertising, and in other marketing communications, don’t use it in text. A mix of uppercase and lowercase characters gives words familiar shapes that help readers scan more efficiently. All-uppercase text just looks like a rectangle, so it’s harder to read.
Example
THIS SENTENCE IS ALL UPPERCASE AND NOT VERY EASY TO READ, DON’T YOU AGREE?

Don’t use all-lowercase text. Capital letters help readers recognize that a new section or thought is beginning. All-lowercase text takes away that helpful cue.
Example
this sentence is all lowercase. or is it a sentence? it's hard to tell with no capital letters.

Learn more To learn more about proper nouns, see Nouns and pronouns. To learn more about capitalization, see Capitalization.