July 4 is celebrated as Independence Day in the United States because it marks the adoption of the Declaration of Independence on July 4, 1776. This document, primarily authored by Thomas Jefferson, declared the thirteen American colonies free from British rule. The day has since become a national holiday, symbolizing American freedom and independence, and is celebrated with various festivities, including fireworks, parades, and barbecues. In the movie "Independence Day," the date also serves as a pivotal moment when humanity unites to fight against an alien invasion.

In the movie "Independence Day," the events take place in 1996 when Earth faces an alien invasion on July 4th. The film does not explicitly mention the date of the next Independence Day, but if we consider the year 2025, it would be the 249th Independence Day in the United States, as Independence Day is celebrated on July 4th each year since 1776. Therefore, 2025 is not the 79th Independence Day; it is actually the 249th.

On July 4, 1776, the Second Continental Congress officially adopted the Declaration of Independence, marking the thirteen American colonies' assertion of independence from British rule. Drafted primarily by Thomas Jefferson, the document proclaimed the colonies' right to self-govern and outlined the philosophical justification for independence, emphasizing unalienable rights such as life, liberty, and the pursuit of happiness. This date is now celebrated annually in the United States as Independence Day, symbolizing the birth of the nation.

In the movie "Independence Day," the central event occurs on July 2, 1996, when alien forces invade Earth. The title refers to the date of July 4, 1996, which is when the humans launch a counterattack against the aliens, aiming to reclaim their planet. Therefore, the film does not pertain to either August 14 or 15; those dates are significant for Pakistan and India’s independence celebrations, respectively.