Even if it doesn’t seem like it, capital letters communicate actual meaning to your readers, so it’s important to learn how to use them correctly. Poor capitalization makes your writing confusing and difficult to decode, which makes people have to slow down and spend extra time processing what you’ve put in front of them. It’s one thing to not capitalize when sending a short text to a friend or to simply trust that your phone’s autocorrect will add capital letters when needed,^[1] but when you’re typing out a 1500-word essay, repeated mistakes in capitalization can take a toll on your reader’s patience.

Here’s a list of the most common places where you need to make sure you use capital letters in your writing. Some of them might seem basic or obvious, but I guarantee you I’ve seen all of these mistakes in submitted student drafts, so it’s probably best to review them all to make sure you’re ready to go.

The first word of a sentence

Whenever you start a new sentence, you need to put a capital letter at the beginning of that first word. There are very few exceptions to this rule, so just get used to doing it every single time.

The word “I”

Every time you write the word “I” (referring to yourself or the person speaking), you need to capitalize it. Always. Just get used to holding that shift key every time you write it. If I had to guess, this would probably be the biggest consequence of texting without worrying about capitalization.

Names

This should be an obvious one, too, but I still get essays with names that don’t start with a capital letter. The name of a person^[2] is always capitalized except for very rare instances where someone, typically a well-known figure of some kind, uses a non-capitalized form of their name as part of their personal or professional style, such as e e cummings, will.i.am, or bell hooks.^[3]

Places

This one goes along with the previous rule. Whenever you use the name of a place, that name begins with a capital letter. If the name of the place includes a common noun (such as “street,” “river,” “lake,” etc.), then that word is also capitalized if it’s part of the name.

You also need to capitalize the names of areas, even if they’re not official names printed on a map, such as the Middle East or the Midwest. This can be slightly confusing, because we normally don’t capitalize directions, like “north” or “southwest.”

Nationalities, ethnicities, religions, and languages

This rule is also related to the one before, because the words that describe where people come from, the groups they belong to, religions they follow, and the languages they speak are always capitalized. So, any adjective describing a person’s nationality (i.e., the nation they come from, e.g., “American,” “Czech,” or “Danish”) or ethnicity (i.e., the cultural background a person has, independent of their national citizenship, e.g., “African American,” “Hispanic,” or “Maori”) needs to have a capital letter. In addition, any noun or adjective describing a person’s religion (e.g., “Catholicism” and “Catholic,” “Judaism” and “Jewish,” or “Buddhism” and “Buddhist”) or language (e.g., “English,” “Tagalog,” or “Xhosa”) should also start with an uppercase letter.

Dates and times

Most of the words associated with dates are capitalized because they give the names of different time periods. All of the days of the week, like “Monday”^[4] and “Saturday,”^[5] need a capital letter, as do all the names of the months, such as “February”^[6] and “June.”^[7] The names of holidays and other special days are also capitalized—for example, “Halloween,” “Ramadan,” and “Chinese New Year”—including the word “day” when it’s used as part of the name of the day itself, as in “Thanksgiving Day” or “Mother’s Day.”

When we give a particular time period a name, we also capitalize the name of that era. We don’t, however, use capital letters when referring to a particular century.

Professional titles

Whenever you use a person’s professional title, such as “Professor,” “Doctor,” or “President,” in front of their name, you need to capitalize it. However, when you use the same word to simply refer to a person with that job or position (without using their name), you don’t start it with a capital letter.

Familial-relationship names

This is a slightly tricky one, because these words can be used in so many different ways. When you use the word that shows someone’s relationship in front of their name, it’s like a title and should be capitalized.

The tricky bit comes when there’s no name after the relationship word. If you use the relationship title in the place of that person’s name, you should capitalize it. If the word comes after a possessive adjective,^[9] then you never capitalize it (again, unless the person’s name is after the title). If you’re just generally referring to people of that relationship, you don’t capitalize the word.

If you’re not sure if you need to capitalize the familial relationship word, try replacing it with the person’s name. If it works, use a capital letter.

Institutions, businesses, and other groups

Whenever you mention the name of an organization, whether that’s a business, university, club, store, team, etc., you need to capitalize that name.

Acronyms and initialisms

An acronym is when you shorten the name of something using the first letter of each word and create a word you can say, like “NASA,” while an initialism is basically the same thing except you can’t say the letters as a word, like in “FBI.”^[12] The difference, though, is not really important because for both of these words, you use capital letters for the entire word.

The only major exception here is when some acronyms become so commonly used that people stop paying attention to the phrase they stand for and start using them as common nouns. This has even happened in words you might know, like scuba^[13] and laser.^[14] You don’t capitalize these words unless they’re at the beginning of a sentence.

Titles

A title is basically a name that is given to a published work, like a movie, a song, an album, a book, an essay, and so on. We capitalize names, so we also capitalize titles. However, it’s a little trickier than that. We don’t capitalize every word in the title, so it’s important to learn the rules that govern which words get capitalized and which don’t.

• First and last word – The first and the last word of the title and subtitle are always capitalized, no matter what kind of word happens to be there.

• The Big Four – There are four main categories of words that communicate the vast majority of the meaning in just about every language: nouns, verbs, adjectives, and adverbs. In a title, these words are always capitalized. This also includes phrasal verbs (e.g., “Turn Up” not “Turn up”) and pronouns (e.g., “He,” “You,” and “They”). If two words are joined together by a hyphen, the second word is also capitalized (e.g., “Self-Esteem” not “Self-esteem”).

• Articles – Articles are never capitalized in a title (unless they’re the first or last word, of course). There aren’t that many articles in English for you to worry about. You really just need to worry about “a,” “an,” and “the.”

• Coordinating conjunctions – You might remember the small set of joining words using the word “FANBOYS.” This acronym helps us remember the seven coordinating conjunctions in English: for, and, nor, but, or, yet, so. These words are not capitalized in titles.

• Prepositions – There’s a bunch of these words in English, and they’re usually used to show the relationship between different nouns or to connect nouns and verbs. A lot of prepositions are really small, such as “in,” “on,” “at,” and “to,” but some of them are longer, such as “between” and “through.” MLA says that all prepositions are written in lowercase, while APA says that if the word has four letters or more, capitalize it.
• Hyphenated prefixes – This is an uncommon one, but if you use a prefix that needs a hyphen to be connected to the noun it modifies, such as “mid-,” “anti-,” or “super-,” then the second part of that word is not capitalized (e.g., “Mid-century” not “Mid-Century”).