1. Erststimme und 2. Zweitstimme
The ballots that Germans receive when they head to the polls on September 24th contains not one, but two choices - one for a district representative and one for a party.
The vote for a candidate on the left side of the ballot is called the Erststimme, or the “first vote,” where a voter selects a candidate to represent his or her district in the parliament.
In the Zweitstimme, or the “second vote,” voters cast their ballot for a political party instead of a single candidate. The second vote appears on the right-hand side of the ballot.
On a German federal election ballot, a voter can make two crosses - one for a candidate and one for a party. Photo: DPA.
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All of the main parties have nominated a Spitzenkandidat, or a “lead candidate” to take them into the election.
The frontrunner for the Christian Democrats (CDU) is current Chancellor Angela Merkel, while the lead candidate for the Social Democrats (SPD) is Martin Schulz.
Leading die Linke (the Left Party) is Sahra Wagenknecht, Katin Göring-Eckardt will take the reins for the Greens and Christian Lindner will take the Free Democrats (FDP) into the election.
Alexander Gauland and Alice Weidel were both nominated as the Alternative for Germany (AfD) party's Spitzenkandidaten for election.
In order for any party to enter the Bundestag (German parliament), it has to win at least five percent of the second vote. This system, called the Fünf-Prozent-Hürde, or the “five percent hurdle,” was set up to prevent smaller splinter parties and extremist parties from entering parliament.
Currently polling at between 9 and 12 percent, anti-immigration AfD is one party that looks set to clear the five percent threshold. The AfD narrowly failed to enter the Bundestag in 2013. At the time they had been campaigning on a eurosceptic platform.
Another party to watch out for in this election in terms of representation in parliament is the pro-business FDP party; it is also expected to win seats this time. In 2013, the party fell short of the bar too.
5. Überhangmandat und 6. Ausgleichsmandat
It is possible for a party to get more direct seats in parliament through the first vote than they deserve according to the party vote.
Since each candidate who wins a district is guaranteed a seat in the Bundestag according to German election law, the party gets to maintain those Überhangmandate or “overhang seats.”
But this would skew the share of seats in the Bundestag based on the percentage of the vote received by the second vote. To make up for this, other parties can then also get more seats, which is called an Ausgleichsmandat, or "levelling seats."
This ensures that each political party's share of seats in the Bundestag is consistent with the number of second votes it received, ultimately making the parliament larger than its base number of seats, up to 630 seats from 598 seats.
7. Große Koalition (GroKo)
A Große Koalition, or a “grand coalition” in Germany describes a governing coalition of the two biggest parties in one parliament.
In the current German government, a Große Koalition (Groko for short) exists between Angela Merkel's CDU party and the SPD party. But neither side is eager to continue this coalition after the election and the smaller parties are expected to tip the balance of power.
Although Merkel is largely predicted to sail into a fourth term, her CDU party and its Bavarian allies, the Christian Social Union (CSU), are expected to fall short of a parliamentary majority.
This means that Merkel's conservative bloc will have to build a coalition with some of the smaller parties, and a Jamaika-Koalition, or a “Jamaica coalition” is one that is highly probable.
Just like a Jamaican flag which is black, green and yellow, a Jamaica coalition would include parties that represent these colours: Merkel's conservatives (black), the left-leaning Greens and the FDP party (yellow).
A three-way tie-up like this would be unprecedented in Germany at the national level and involve some serious negotiating given the stark ideological differences between the parties.
Yet another example of Germany's colour-coded politics, an Ampelkoalition, or a traffic light coalition, describes a coalition government of the SPD (red), the FDP party (yellow) and the Greens.
The term traffic light coalition originates from German politics and has subsequently been picked up by other countries to describe similar coalitions between social democrats, liberals and green.
After the German election, an Ampelkoalition is less likely than a Jamaika-Koalition. Germany's foreign minister Sigmar Gabriel (SPD) supports it though, recently telling broadcaster SWR "I'm a big fan, I'm a social liberal, and at the heart of it I think it's the right coalition.”
Wahltagsbefragung, or “exit polling,” is a form of election research. On election day, interviewers will ask voters when they leave the polling station about their votes. Socio-demographic data and information about how they voted in the previous general election will also be collected.
In Germany, this data is then used in electoral reporting and to a lesser extent, post-election analysis.
On Sunday, polling stations across the country open in the morning and close at 6pm local time. Soon afterward, the country's public broadcasters such as ZDF and ARD will present their exit polls.
In the evening on Sunday, first projections of the election outcome will be announced but it's possible a definitive final result could take until Tuesday.