Capitalization is writing the first word with capital letter, whereas all other words in the sentence are written in small letters.
American capitalization differs in several aspects from British one.
Here are some of the basic rules of American capitalization that you should take into account while writing.
1. The first word of the sentence is always capitalized.
E.g. Derrick has decided to live the country! Where does he want to go?
2. The first word of the direct quotation, except in cases when the quotation is split, is capitalized.
E.g. Peter exclaimed: “It is preposterous!!!” “I do not think so,” Elisabeth replied, “in my opinion he could do this.”
3. All the first words of the lines in poems are capitalized.
E.g. From fairest creatures we desire increase,
That thereby beauty's rose might never die,
But as the riper should by time decease,
His tender heir might bear his memory.
4. The names of individuals, companies, organizations as well as different historical periods and some events are capitalized.
E.g. The UN, the White House, State Department, Winston Churchill, the Republican Party.
5. The names of all geographical places as well as the names of continents, districts, rivers, oceans and lakes are capitalized.
E.g. Great Britain, London, the Persian Gulf, the Pacific Ocean. You should capitalize the compass points, except in cases when the specific region is mentioned.
6. The names of boats, ships as well as the names of aircrafts are capitalized.
E.g. St Louis, Bernard, Caronis.
7. The name of races, nationalities as well as languages are capitalized.
E.g. German, Croatian, French, Hispanic.
8. The names of close relatives, when the name of the member of the family is used as a title are capitalized.
E.g. Uncle Sam, Aunt Christine, Aunt Paula.
9. The professional title of the person, when it is written before his/her name is capitalized.
E.g. General Clark, President Bush, Professor Suttons.
10. All the first letters in the headings of movies, plays and novels are capitalized.
E.g. An Extremely Goofy Movie, The magic Skin.
11. “The” in the names of the periodicals, when it comprises the part of the title is capitalized.
E.g. The Washington Times.
12. First letters in the greetings and salutations, such as "Dear Clare", "Yours ever" are capitalized.
13. Epithets in the names of the places and different persons are capitalized.
E.g. Old Justin, the Foggy Town.
14. The word “I” should always be capitalized.
E.g. Finally. I reconsidered his decision.
15. Biblical names as well the names of sacred places and works are capitalized.
E.g. The Koran, Mathew, Jesus.
16. The names of the days of the week as well as months and holidays (including religious ones) are capitalized.
E.g. Monday, April, Christmas.
17. The names of some definite Courts are capitalized.
E.g. Supreme Court of the United States, Scottish High Court.
18. The name of treaties are capitalized.
E.g. North Atlantic Treaty, Copyright law, Corporative law.
19. Trademarks of goods and services are always capitalized.
20. The names of different geological eras are capitalized.
E.g. Stone Age, Paleozoic age, Bronze Age.
21. The names of all planets and the names of the stars are capitalized.
E.g. Saturn, Jupiter, Mars.
22. Many Latin names of biological and zoological classes, except genera are capitalized.
23. Some abbreviations are also capitalized.
E.g. NATO, UN.