What is July 4?
July 4, also known as Independence Day, is the day in 1776 that delegates from the 13 U.S. colonies adopted the Declaration of Independence, announcing the severing of ties with Britain.
The day has been a federal holiday in the United States since 1941 and is traditionally a day when Americans celebrate with firework displays, parades, concerts and cookouts.
Fireworks
July 4 is known around the country as a day of fireworks. Thousands of communities across the nation organize annual displays of fireworks with one of the most dazzling displays taking place in Washington, the nation's capital.
Fireworks on July Fourth are not new. Congress authorized the use of pyrotechnics as part of Independence Day celebrations in 1777 in Philadelphia, and they have been a popular way to celebrate the holiday every since.
WATCH: Fireworks Safety
Each U.S. state has its own laws governing the sale of fireworks, with many states allowing residents to buy and set off certain types of fireworks at their homes.
Security
As millions of Americans celebrate the holiday, local law enforcement and federal officials are working to ensure the celebrations remain safe.
Police will be out in force in New York City, where the largest firework display will take place. Last year, around 3 million people gathered in the city to celebrate the holiday. A large police presence is also expected in Washington, where hundreds of thousands of people are set to gather to watch fireworks and listen to a concert at the Capitol.
This week, police in Ohio arrested a man they say was planning to detonate a bomb at Cleveland's Fourth of July celebrations. Officials say Demetrius Pitts, an American-born citizen, had expressed allegiance to the al-Qaida militant group, and had also intended to target other locations in Cleveland and Philadelphia.
History
On July 2, 1776, the Continental Congress voted in favor of independence. Two days later, delegates from the 13 U.S. colonies adopted the Declaration of Independence, drafted by Thomas Jefferson.
WATCH: Why does the U.S. celebrate July 4th?
Some constitutional scholars argue that Americans should actually celebrate on July 2 — not July 4 — because of the historic vote.
The U.S. rebellion against the British began a year earlier in 1775, and fighting continued until the United States and Britain signed the Treaty of Paris in 1783, which formally recognized the independence of the United States of America.
