The two-day G20 Leaders' Summit has started in the Argentine capital Buenos Aires. As the event gets underway, this article will offer a brief overview of the group. 

The G20 or the Group of Twenty, is an international bloc made up of governments and central bank governors from economic powerhouses in Asia, Africa, Europe, and the Americas. 

The G20 summit dates back to 1999. It was convened for leaders to discuss international finance policy and address issues that go beyond the responsibilities of any other organization. 

The members enjoy 60 percent of the world's land area and two-thirds of the global population.

G20 member countries' economies account for around 85 percent of the global GDP, and nearly 75 percent of the global trade volume.

The group's heads of government and heads of state of have met annually since 2008. The leaders have focused particularly on international economic cooperation since that year's international financial crisis. The group's agenda has expanded, and it now also hosts separate meetings for finance ministers and foreign ministers. 

This year's gathering in Argentine capital Buenos Aires marks the summit's 10th anniversary. Under the theme of “Building Consensus for Fair and Sustainable Development,” the G20 leaders are expected to share their views in the fields of trade and investment, digital economy, infrastructure, and climate change.