Protesters have been rejoicing in their new freedom because three decades of authoritarian rule have been swept away and the Egyptian military is now running the country.
But the armed forces may not be in charge for long.
Shortly after Mubarak's resignation, a military spokesman announced the army will not act as a substitute for a legitimate government.
He added that the armed forces will eventually introduce changes that all Egyptians want.
The military also praised Mubarak for his contribution to the nation.
A rally in Chicago is scheduled for Friday night at the Egyptian Consulate on Michigan Avenue to commemorate this historic moment.
For many devout Muslims in Chicago, Friday's call to prayer was not only a chance to commune with God but to celebrate. "This is the first time in my life that I'm proud that I'm an Egyptian," said Adam Ali.
That sense of pride permeated the attitudes of the many Muslims who hail from other Arab countries.
"It's think a lot of good feeling for a lot of Muslims, especially in that part of Egypt democracy was needed," said Iftekhar Sharif.
"I was very surprised because yesterday, with that speech I thought he's not going to move from his position. And today a lot of surprise by he decides to go away," said Moroccan-American Marouane Ghaila.
For a range of Arab men who mostly skipped the call to join their brethren at the Muslim Community Center -- what has happened in Egypt indicates time is running short for other authoritarian rulers in the Mideast
"Mubarak is gone and the next one is going to be Yemen. I hope this change goes to all the dictatorship and Muslim dictatorship because almost all the Arabic and Muslim countries are directed by dictators," a man said.
There are many Americans in Cairo witnessing the massive protests first-hand. Photojournalist Matt Cassel from Chicago's North Side has been taking pictures to document the events happening in Egypt. He has been in Cairo since the unrest began and said the feeling there was one of utter victory after Mubarak left office.
"Already in our neighborhood over here, we can hear cars are honking, people are congratulating each other, kissing each other. It's a celebration," Cassel said.
He also said covering the developments had been "amazing."
"I know the country. I know the people here, and I know how much frustration and anger they have with their government. Finally, he's gone. The dictator of their country is gone, and now they can work to establish some kind of a more Democratic system and have some actual rights in their country," said Cassel.
Celebrations in one of Chicago's North Side neighborhoods were still muted late Friday morning as news of Mubarak's resignation was still spreading.
That was expected to change as the day went on.
Still, the owner of one of Chicago's most popular Egyptian restaurants told ABC7 that Mubarak's rule was obviously a long-standing concern of the people of Egypt. He said to actually realize that Mubarak had stepped down after 30 years in power --despite the fact that there had been 18 days of demonstration-- is really hard for people to believe.
Others said they thought Mubarak's resignation was inevitable. One home care worker said she was more than relieved that Mr. Mubarak finally realized the regime was changing in Egypt.
"That's good, because these people are very hungry, and they need some help. That's all I could say. I'm very happy. I'm very happy he stepped down. For 30 years, he has been president," Jenny Zutaut said. "I'm very happy because Egyptian people are very hungry and very poor people. They need some help."