Afghanistan is holding parliamentary elections on Saturday despite deep security concerns and ongoing fighting in as many as 20 out of the country's 34 provinces.

The polls come amid a particularly vicious campaign by the Taliban and the militant Islamic State (IS) group, which have been staging near-daily attacks. Besides the security challenges, there have also been concerns over the transparency of the vote and for the first time, the election commission has equipped polling stations with biometric identification systems.

Take a look: Afghan-style democracy faces test in legislative election

Here is a look at the elections, the figures and key issues in the vote:

How many seats, how many candidates and polling stations?

There are 2,565 candidates vying for 249 seats in the lower house of parliament, including 417 women candidates.

Voters will be able to cast ballots at more than 19,000 polling stations in 33 provinces. Of those, the elections commission says as many as 11,667 polling stations are reserved for men and 7,429 for women, while 46 will serve Afghan nomads, known as Kochis, and 22 will serve minority Sikhs and Hindus.

The Kochis have 10 parliament seats reserved for them while the Sikhs and Hindus jointly have one seat.

However, security fears have forced the election commission to close about 2,000 polling stations.

Major players and political parties

A few parties have emerged in opposition to the current national unity government of Afghan President Ashraf Ghani and Chief Executive Officer Abdullah Abdullah, but none can be considered major players as most candidates in the vote are running as independents.

Afghanistan's parliament includes both a lower and an upper house, but only members of the lower house are directly elected. The upper house consists of a mixture of parliamentarians chosen from local councils and those appointed by the president, as well as members elected in district elections.

Legislature passed in the lower house has to be approved by the upper chamber.

Dispute in Ghazni province

Elections will not take place in eastern Ghazni province amid an ongoing dispute over how to divide its electoral constituencies to ensure a more balanced ethnic representation. Lawmakers elected from Ghazni in 2010 will retain their seats until the province is able to hold a vote.

In the last elections, eight years ago, minority Hazaras won all the seats from Ghazni, leaving majority Pashtuns and also Tajiks without representation as voting wasn't held in their areas, which are mostly controlled by the Taliban.

No district council elections this time?

Initially, elections for district councils were supposed to take place at the same time as parliamentary elections but the Independent Election Commission delayed that vote because only a tenth of the country's 400 districts had enough male and female candidates step forward to run in district races.

Security fears and violence are top reasons why so few wanted to run for district seats. Other reasons include high illiteracy rates among Afghans living in districts.

Eligible voters

Around 8.8 million people have registered to vote.

Though there hasn't been a census for more than 30 years, Afghanistan's population is estimated to be more than 30 million. Of the registered voters, 64 per cent are men and 34 per cent are women; the remaining 2 per cent are Kochis, Sikhs and Hindus.

Security arrangements

More than 50,000 members of the Afghan security forces will be deployed to secure polling stations.

Afghan officials have announced three levels of security belts at each polling centre. Police and members of the intelligence force will make up the first two belts, covering a distance of three to five kilometres from polling centres.

The third security belt will be patrolled jointly by police and Afghan army. Officials say elections won't be held in 10 districts that are completely under Taliban control, including five in southern Helmand province, the Taliban heartland.

The other five districts include two in northeastern Badakhshan province and one each in northern Baghlan, Sari Pul and southern Zabul province.

Violence ahead of elections

There have been deadly attacks against candidates and campaign rallies, both by the Taliban and IS militants. Since the 20-day campaign period began, at least two candidates and over 34 civilians have been killed in such attacks, including suicide bombings, motorcycle bombs and drive-by shootings.

In the run-up to campaigning, five candidates were killed and two were abducted, their fates unknown. Also, Afghan security forces accidentally killed three bodyguards of an independent candidate during a raid on a house near his residence.

On Thursday, at least two senior Kandahar provincial officials were killed by one of their own guards during a meeting to discuss security ahead of the vote.

Taliban warnings

The Taliban, who have been fighting Afghan and Nato forces for more than 17 years, have condemned the elections and warned candidates and Afghan security forces they would be targeted.

They have also warned teachers and students not to participate in the elections and not to allow schools to be used as polling centres.

Civil society and election observers

More than 400,000 civil society activists, independents and members of political parties, as well as national and international observers and representatives from media outlets will follow the polling day.

What is at stake?

The Afghan government is keen to prove it's capable of holding these elections despite prevailing security challenges. The vote was originally scheduled for 2015 but the situation was too unstable at the time.

Politically, there was a crisis following the 2014 presidential elections, and Nato forces had only just handed over security to Afghan forces at the end of 2014.

Now, the government wants to send a message to the Taliban — who are engaging in separate negotiations with the United States on a possible political settlement — that its institutions are functioning and that if the Taliban decide to come to the negotiating table, they will have to deal with a government and a political process that's acceptable to the majority of Afghans.