France holds the first round of its presidential elections nationwide on Sunday, which — provided no candidate gets more than 50 percent of the vote — will be followed by a second and final round on May 6. Here is how the first round works and what's at stake:

— WHAT IS HAPPENING: French citizens go to the polls to choose the country's president. Just over 43 million people are eligible to vote. The new head of state will begin a fixed five-year mandate until 2017.

— WHEN: Polling stations in municipal buildings around the country will be open from 8 a.m. to 6 p.m. In some urban areas polls remain open until 8 p.m.

French electoral law outlaws any publication of voting estimates before all polls close at eight. The idea is that those voting late should not be influenced by knowing the likely outcome.

The Paris prosecutor's office this week said that they'll slap transgressors who publish the results before 8 p.m. with a fine of up to €75,000 ($98,000).

Voters in some French overseas territories will vote on Saturday, although the results won't be made known until Sunday night.

— CANDIDATES: There are ten candidates on the first round ballot paper.

The incumbent president, conservative Nicolas Sarkozy, is running to be re-elected for a second, and final, term.

His main adversary is Socialist Francois Hollande, who polls show in the lead. Hollande hopes to become France's first socialist president in 17 years .

Polling at third and fourth are, respectively, Marine Le Pen of the far-right National Front, and leftist Jean-Luc Melenchon of the Left Front.

— ISSUES: Jobs are the primary concern of the French, with unemployment near 10 percent. The stagnant economy is also an issue with rival candidate proposing alternative solutions: Sarkozy has stressed austerity, Hollande wants to stimulate growth.

— WHY IT MATTERS: The choice that French people make will affect not only France, Europe's second largest economy, but is likely to also have a profound impact on the European Union and its attempts to manage the eurozone debt crisis.

France is also a permanent UN Security Council member and nuclear power and has troops from Afghanistan to Congo. Presidential candidates plan to withdraw French troops stationed in Afghanistan under different timetables.