Global leaders have descended on New York City for the 72nd edition of the United Nations General Assembly.
Those in the know will be keeping a close eye on what is sure to be a hectic week of global diplomacy and decision-making.
Here are a few key numbers to help you get up to speed:
The UN General Assembly, which serves as the "main deliberative, policy-making and representative organ" of the UN is made up of 193 member states.
Although the decisions it makes are not legally binding, meetings at the summit can set the agenda for crucial UN Security Council actions down the line.
Over the course of the week, more than 100 heads of state are expected to join the talks, with delegates and foreign ministers filling in for those who can't make the trip.
Several new faces will be making their UNGA debut -- most notably US President Donald Trump, who is a long-standing, outspoken critic of the UN.
Trump and US Ambassador to the UN Nikki Haley led a meeting that emphasized the need for reforms to the organization on Monday -- an initiative welcomed by UN Secretary-General Antonio Guterres.
Fellow newcomer Emmanuel Macron, President of France, is set to present a speech very different from his US counterpart, having pledged to promote the Paris Agreement on climate change.
UK Prime Minister Theresa May will be attending for the second time. In her maiden speech last year, May said that the UK's vote to leave the EU was not a vote for isolationism, and pledged that the UK would remain an "outward-facing, global partner at the heart of international efforts to secure peace and prosperity for all our people."
But some world leaders won't be attending.
Venezuelan President Nicolas Maduro, whose country is caught up in a major economic and humanitarian crisis, will be staying away. Maduro's government has been widely criticized by the US and the UNHCR for human rights abuses since anti-government protests broke out there in April.
Also skipping this year's event are Mexico's Enrique Pea Nieto, Russia's President Vladimir Putin, German Chancellor Angela Merkel, China's President Xi Jinping, India's Prime Minister Narendra Modi and the recently resigned Prime Minister of Pakistan, Nawaz Sharif.
From Tuesday, the floor is open to all delegates, with Trump scheduled to speak second after Brazil's president, Michel Temer. Turkmenistan is scheduled to speak last on September 25.
All speakers are asked to limit their remarks to just 15 minutes -- with more than 193 speeches totaling 48 hours of talking scheduled within a few days, even world leaders have to keep it short.
Speech times aren't 100% clear -- the UNGA schedule is only a guideline since leaders can trade slots, especially if they get caught up in New York City's notorious traffic.
The podium is prime real estate for presidents, prime ministers and dignitaries wanting to air grievances and reinforce political positions.
And while there's no guarantee that the rest of the world will be listening with bated breath -- some exhausted audience members have been spotted napping or catching up on emails during the speeches -- there's plenty of scope for drama.
In 2012, Israeli Prime Minister Benjamin Netanyahu asked the assembly to draw a "clear red line" to prevent Iran from developing nuclear weapons. Holding up a cartoon-like drawing of a bomb, he drew a red line below the fuse.
Iranian President Mahmoud Ahmadinejad's 2011 speech was so egregious to some dignitaries that a mass walkout ensued. Delegates from the US, France, Germany and the UK left during the speech, in which Ahmadinejad repeatedly condemned the US, and said that some countries use the Holocaust as an "excuse to pay ransom ... to Zionists."
In 2009, Libyan leader Moammar Gadhafi launched a blistering attack on the Security Council, blamed the UN for failing to prevent 65 wars since its founding, suggested that the swine flu virus was a military tool or corporate weapon, and hinted that Israel was behind President John F. Kennedy's assassination.
Gadhafi's tirade went on for 96 minutes, but it wasn't the longest on record; in 1960, Fidel Castro gave a UNGA speech that lasted four hours.
All 193 member states contribute to the UN's budget, totaling $2.58 billion this year. Financially the United States contributes the most overall, comprising 22% of the total budget ($55.9 million this year).
That economic sway is one of many reasons that the US led the conversation over the direction of the organization's future on Monday.
Japan contributes the second highest amount, covering 9.68% of the total amount of the UN's budget, followed by China (7.92%), Germany (6.39%), France (4.86%) and the UK (4.46%). More than 130 countries contribute less than 0.1% of the total share.
High on the UNGA agenda this year is the growing humanitarian crisis and escalating violence unfolding in Myanmar.
According to UNICEF, since August 25 more than 400,000 Rohingya -- 60% of them children -- have fled to Bangladesh.
Last week, UN human rights chief Zeid Ra'ad Al Hussein described the actions of Myanmar's armed forces as a "textbook example of ethnic cleansing." Myanmar has denied this, claiming security forces are carrying out counterattacks against "brutal acts of terrorism."
In the UNGA opening remarks last week, Secretary-General Antonio Guterres called on Myanmar's government to recognize the Muslim minority's rights in Myanmar and asked the authorities "to suspend military action, end the violence, uphold the rule of law, and recognize the right of return of all those who had to leave the country."
But Myanmar's de facto leader, Aung San Suu Kyi, won't be present to respond to Guterres' call. Last week, Suu Kyi called off her trip to New York, with a spokesperson blaming the situation in Myanmar's Rakhine state and the possibility of an impending terrorist attack in the country for her decision.
Last week, North Korea fired a ballistic missile over the northern Japanese island of Hokkaido, its 15th missile test since February.
Each launch is a chance for the rogue nation to perfect its technology, and its nuclear weapons program is sure to be a hot-button topic at the UNGA.
The 15-member UN Security Council unanimously adopted a US-drafted resolution last week, imposing new sanctions on North Korea to limit oil imports, ban textile exports, end overseas labor contracts and sanction North Korean government entities.
In his opening remarks, Guterres stressed that countries must work together to resolve the North Korea issue: "The solution can only be political. Military action could cause devastation on a scale that would take generations to overcome."
"Hurricanes and floods around the world remind us that extreme weather events are expected to become more frequent and severe, due to climate change," Guterres said in his opening speech.
In 2015, 197 countries signed up to the Paris Agreement, a landmark accord aimed at cutting emissions to keep global temperatures from rising by more than 2 degrees Celsius above pre-industrial levels. 160 nations have ratified the deal so far.
In June, Trump said the US would drop out of the deal, putting it at odds with nearly every nation in the world, except for Syria and Nicaragua. The US is the second worst carbon polluter after China, according to the World Bank.
On Saturday, the White House said that Trump still plans to withdraw unless big changes are made to the carbon emissions pact, a major point of contention between the global giant and its allies.
One of the UNGA's key objectives is to create gender equality at the UN by 2028.
Guterres says it is time the organization leads the world by example; over half of his appointments to the UN's senior management group -- 17 so far -- have been women.
According to a 2016 UN report, 143 nations guarantee equality between men and women in their constitutions, while 52 have not taken steps to achieve it in practice.
Yemen is ranked as the worst country in the world for gender equality in the last decade, according to the World Economic Forum's annual Global Gender Gap Index.
Pakistan, Syria, Saudi Arabia, Chad and Iran are among the worst nations in the world to be born a girl, according to the WEF.
The countries that score highest for gender equality worldwide are Iceland, Finland, Norway, Sweden and Rwanda.