What is the difference between title case and sentence case?

Title case capitalizes most words in a title; sentence case capitalizes only the first word and proper nouns, like a normal sentence.

Why are capital letters called uppercase?

In hand-set printing, capital letters were kept in the upper of two type cases and small letters in the lower one.

Is all caps harder to read?

For long passages, generally yes. GOV.UK’s style guide advises against block capitals for large amounts of text because they are hard to read. Short labels and acronyms are fine.

Should website headings use title case or sentence case?

Either works if used consistently. Many organizations, including GOV.UK, use sentence case for headings and page titles because it is simpler and reads naturally.

Is it rude to type in all caps?

Online, all caps is widely read as shouting. Reserve it for acronyms or occasional emphasis.

Illustration of the same word shown in capital letters, small letters and capitalized form

Text & writing

Uppercase vs. Lowercase vs. Title Case

Uppercase, lowercase, title case, and sentence case are four ways of using capital letters, and each has settings where it is expected. This guide explains what each style is, where the names come from, where each is conventionally used, and why a growing number of organizations favor sentence case for headings.

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The four styles at a glance

The four styles at a glance comparison
Style	Example	What is capitalized
UPPERCASE	THE LORD OF THE RINGS	Every letter
lowercase	the lord of the rings	No letters
Title Case	The Lord of the Rings	Main words; short words such as “of” and “the” usually stay lowercase unless first or last
Sentence case	The lord of the rings	The first word and proper nouns only

Where the names come from

The terms come from hand-set printing. Metal letters were stored in cases, with capitals kept in the upper case and small letters in the lower case — hence “uppercase” and “lowercase”.

Where each style is used

Uppercase: acronyms and initialisms (NASA, HTML), short labels and signs, and emphasis in very small doses. Long passages in capitals are harder to read — the UK government’s GOV.UK style guide specifically advises against block capitals for large amounts of text.
Lowercase: ordinary running text apart from sentence starts and proper nouns; also usernames, hashtags, email addresses, and some brand styling.
Title case: titles of books, films, and songs, and headlines or headings in publications that follow AP, APA, Chicago, or MLA title rules.
Sentence case: running text, and headings in many modern publications and interfaces. GOV.UK tells writers to always use sentence case, even in page titles, and APA uses sentence case for the titles of works in reference lists.

Choosing between title case and sentence case for headings

Both are correct when applied consistently. Title case can look more formal and is traditional for published titles. Sentence case involves fewer rules — there is no list of minor words to remember — reads more like normal text, and makes proper nouns stand out because they are the only capitalized words.

Whichever you choose, apply it to every heading at the same level. Mixing styles is more noticeable to readers than either choice.