Climate talks in Paris have ended with the agreement of an “historic” climate deal.

It took two weeks – or 21 years, depending on how you look at it. Here’s what we’ve learned.

1. It’s the first universal climate change agreement

The world’s first universal climate change agreement has been secured, fulfilling a pledge by countries four years ago at talks in Durban, South Africa to do so.

2. We’re aiming for net zero greenhouse gas emissions for 2050 and beyond

A Filipino boy passes by a slogan during a rally in Manila
(Aaron Favila/AP)

It aims to hold global temperature rises to “well below” 2C above pre-industrial levels and to keep increases to 1.5C, by effectively reducing greenhouse gas emissions to net zero by the second half of the century.

3. This has been 20 years in the making

Valentine's Day card urging President Bush to sign the Kyoto Protocol
(Ron Edmonds/AP)

Securing the deal is seen as the culmination of more than 20 years of work under the United Nations climate change convention, and comes after the Kyoto Protocol which only covered emissions from some countries and a failed bid in Copenhagen to achieve a comprehensive agreement.

4. We witnessed the biggest gathering of world leaders at a UN event

U. S. President Barack Obama attends a group photo session at the World Climate Change Conference 2015

The attendance of around 150 heads of state and government on the first day of the talks to urge action on climate change was the biggest gathering of world leaders at a UN event on a single day, according to officials for the organisation.

5. But they weren’t the only ones in attendance

Leonardo DiCaprio adresses to the audience during a meeting with Mayors to push for local actions to fight climate change at Paris city Hall
(Francois Mori/AP)

Big names have attended the talks along with ministers and negotiators, including former US vice president Al Gore and Hollywood star and former California governor Arnold Schwarzenegger, while actor Leonardo DiCaprio expressed his concerns over climate change at an event across town in Paris.

6. It’s been rhetoric-heavy

French President Francois Hollande, right, French Foreign Minister and president of the COP21 Laurent Fabius
(Francois Mori/AP)

There has been no shortage of rhetoric at the talks, with the Prince of Wales evoking Churchill by describing the negotiators as the “few” on whom the world depended, French foreign minister Laurent Fabius quoting Nelson Mandela and French president Francois Hollande referencing Neil Armstrong with his “major leap for mankind” speech.

7. Words matter

A mix-up over “shall” and “should” in the legal text delayed the agreement going through at the 11th hour and for a moment looked like it could even crack the whole thing open. But it was fixed, and the deal was done.

8. The French delivered a master-class in diplomacy

French Foreign Affairs Minister Laurent Fabius delivers a speech at the COP21
(Eric Feferberg/AP)

By steering the negotiations through some tense times, giving countries often considered “difficult” or outsiders key roles and balancing the interests of 195 different nations in securing the final deal, the French diplomats had a big part to play.

9. Sleep? What’s that?

No one should expect to get much sleep at climate negotiations. The UK delegation even had sleeping bags in case they were needed, and Energy and Climate Change Secretary Amber Rudd admitted she had only caught a few hours sleep in the last day or so of intense negotiations.

10. Protesters are creative

Activists wait with their bear costume before a demonstration near the Eiffel Tower
(Matt Dunham/AP)

Even though a massive march through the centre of Paris at the beginning of the talks was cancelled over security concerns, campaigners made sure their voices were heard, in ways ranging from a moving protest of thousands of pairs of shoes to represent the cancelled march to a roaring giant puppet polar bear.