Northern Ireland politics doesn't have to make your head hurt

The main political parties in the rest of the UK don't have any seats in Northern Ireland.

So, there must be something very unusual happening there.

Northern Ireland is different because the voters there are divided differently than in the rest of the UK.

Instead of, say, "left wing" or "right wing" in Northern Ireland the two main political sides are distinguished by culture, history and religion.

It's important to understand this before trying to get your head around the way people vote.

Broadly speaking, one side is in favour of Northern Ireland's union with Great Britain.

The political parties are unionist and draw support mainly from Protestants.

The other side are nationalists, who are mainly Catholic.

They want Northern Ireland to be joined with the Republic of Ireland, making one Irish nation.

There are smaller political parties who consider themselves "cross-community".

Thirty years (1968-1998) of bitter fighting between the two communities is referred to as "The Troubles".

More than 3,600 people were killed. 50,000 others were injured.

You can assume, therefore, with an overall population of less than two million that very few families have gone unaffected.

Republican militant groups (paramilitaries) like the IRA and INLA wanted Northern Ireland to join with the Republic of Ireland.

Loyalist paramilitaries, such as the UDA/UFF and UVF, wanted the union to remain in place.

Housing, policing, you name it - if it's a public service it's been affected by the conflict.

In 1998 the world-famous Good Friday Agreement was signed.

It laid plans for paramilitaries to hand over weapons and allowed some prisoners to be released.

It also led to a reform of the police service, because the old police force - the RUC - wasn't trusted by many nationalists and Republicans.

The peace deal set up Northern Ireland's devolved government, which is based at Stormont on the outskirts of Belfast.

The agreement wasn't easy to implement.

However over the years massive steps forward have been made.

Community work and increased political cooperation has eased tensions and, critically for most people, the fear of violence and bombings has all but gone.

Belfast is still divided into neighbouring Catholic and Protestant pockets.

The lines between them are sometimes marked with "peace walls". These high barriers, with fences on top, have gates that are locked at night to keep rival communities apart.

Some feel the walls keep them safe, others feel the walls keep them divided.

Because the two sides identify so closely with different religions, faith plays a very large part in Northern Irish politics.

Unlike in the rest of the UK, gay marriage has not been made legal.

There are also much tighter laws on abortion.

Newsbeat has been speaking to some young voters who feel frustrated. They say politicians spend too much time arguing about the past and not enough is done to "modernise" the country.

For example, Newsbeat recently reported how Northern Ireland is the only place in the UK where there is no specific law against revenge porn, and no consultation in the pipeline.

But others feel that more needs to be done to ensure that they get "justice" for what happened in the Troubles - or at least acknowledge that they were victims.

The other thing to know is that Northern Ireland's Assembly (in Stormont) has been designed in a way that parties have to work together.

They call it "mandatory coalition" and although it encourages the sides to co-operate, it also means decisions are often made slowly as everything has to be talked through to ensure everyone is happy.

And if at this stage you're thinking "why don't they just get over it and move on?" then you are underestimating the effects of "The Troubles".

Fathers, mothers, uncles, neighbours have been murdered on both sides.

And although most people have tried to get on with their lives and definitely value the peace they now have, few have actually forgotten what happened.

Emotions can still run high in some areas, especially when you add in the everyday problems of modern politics like unemployment, deprivation, the recession and cuts to public services.

Northern Ireland's politicians still have to deal with these issues, but the backdrop of split communities makes things that much more complicated.

In the 2015 General Election the Democratic Unionist Party (DUP) will be fielding 16 candidates.

The party is led by First Minister Peter Robinson and defends Northern Ireland's links with Britain.

In the 2010 election the DUP won eight MPs making it the biggest party in NI and the fourth biggest group in the Commons.

Sinn Fein is the party which had links to the IRA.

They are often referred to as being part of the "Republican movement".

They will stand in all 18 constituencies.

In 2010 they had five MPs elected.

They refuse to sit in the House of Commons because they believe that the UK parliament has no authority over Northern Ireland.

However, they do carry out work for their constituents and have offices in Westminster.

The SDLP who call themselves the "principle party for the nationalist community" and the Alliance Party who stand for "cooperation between Nationalist and Unionist" will also stand in every area.

The SDLP had three MPs last time around. Alliance had one.

The Ulster Unionist Party is standing in 15 constituencies.

It used to be the biggest Northern Ireland party at Westminster but a decade ago they were overtaken by the DUP and in 2010 did not win any seats.

The third biggest unionist party is the Traditional Unionist Voice (TUV).

Its founder and leader split from the DUP because they went into a power-sharing government which included Sinn Fein.

They will stand in seven areas.

The Green Party is putting forward five candidates.

UKIP will be standing in 10 seats.

The Conservatives are running in 16 areas.

The Workers Party will run five candidates.

CISTA, which wants a review of drug laws, is standing in four constituencies.

People Before Profit has put forward one candidate in Belfast. And there will be five independent candidates overall.

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