The BRICS nations are meeting Thursday for an economic summit in India. If you’re scratching your head over that acronym, here’s a quick explainer on who the BRICS members are and why they’ve teamed up.The BRICS stands for Brazil, Russia, India, China and South Africa. The five countries are generally characterized as rising powers that have sought more influence to match their economic prowess.Together, the group accounts for 45% of the world’s population and a quarter of its economy -- $13.5 trillion, according to the Associated Press. Brazil, Russia, India and China began meeting in the last six years, with their first official meeting three years ago. South Africa joined two years ago, though many experts question whether it has the same global clout as the other four countries.The BRICS group has been heralded as an alternative to the established powers. Russian Foreign Minister Sergei Lavrov called it "one of the most significant geopolitical events since the beginning of the new century ... a new model of global relations overriding the old East-West or North-South barriers.”The countries have met to tackle issues  including terrorism and climate change and pushed for a bigger voice in the World Bank and other global financial institutions. They have stated that” and tackling the challenges of modernization. One of the proposals they’ll tackle in India: a new, alternative development bank to lend money across the globe."It’s a political force multiplier,” said David Rothkopf, CEO of Foreign Policy magazine and the author of "Power Inc.” "They don’t want their futures dictated to them by richer nations from the established leadership that emerged out of the Second World War.”For instance, the BRICS -- minus Russia -- dramatically reshaped the climate change deal that the United States was pushing in Copenhagen roughly two years ago, said Christian Deseglise, an adjunct professor who launched BRICLab, a forum at Columbia University to study the emerging powers. But not everyone is convinced that these diverse countries make sense as a political force. Jim O’Neill, the economist who first coined the term "BRIC,” argues that besides being big and having lots of land and people, these countries have little in common. He’s also skeptical of South Africa’s inclusion.Some experts argue that the alliance is an artificial one, pointing out that the acronym was devised by a Western economist. The BRICS members are often rivals rather than allies: India, for instance, has been alarmed that the Chinese might use a "string of pearls” strategy to establish bases on neighboring islands. Brazil is leery of becoming too economically dependent on China.The clashing ideals of the BRICS also came to the fore last year when South Africa, where the memory of apartheid is still vivid, failed to issue a visa to the Dalai Lama, apparently wary of offending China. Former Archbishop Desmond Tutu denounced the government for siding with oppressors, calling it "disgraceful.”But Rothkopf points out that countries don’t need to agree on everything to get things done. "It is impossible to imagine addressing global issues without them in the room,” he said.