With the rising prominence of groups such as the alt-right throughout US President Donald Trump's campaign and election, differentiating between the various currents that comprise the American far right has become challenging.

Media outlets and political commentators have struggled to define the parameters, often inaccurately labelling high-profile far-right figures as part of the alt-right.

Al Jazeera has broken down some of the factions of the American far right, explaining their similarities and differences.

Alt-right

The alt-right is a loosely knit coalition of far-right groups that includes populists, white supremacists, white nationalists, neo-Confederates and neo-Nazis. Many alt-rightists promote various forms of white supremacy, white nationalism, anti-Semitism and Holocaust denial.

The term "alt-right" was first coined by US white supremacist Richard Spencer in 2008 to provide an alternative to the neoconservative politics that dominated the Republican Party establishment in recent decades.

Shortly after Trump's November 2016 victory in the presidential elections, the movement became a household name in the US when Spencer led an audience in chants as they performed Nazi-like salutes. Spencer roared: "Hail Trump! Hail our people! Hail victory!"

The movement promotes what it calls "white identitarianism", a worldview that advocates European racial and cultural hegemony. Alt-rightists often cite racial science as vindication for their views.

Researchers and experts note that sexism is as integral to the alt-right as racism, pointing out that there are few females among the cadres of the movement. One exception is Brittany Pettibone, a contributor at AltRight.com and Red Ice, a Sweden-based white nationalist video and podcast platform.

Among the groups involved in the movement are: Spencer's think tank, the National Policy Institute; the National Socialist Movement; the neo-Confederate League of the South; Identity Evropa, the white supremacist group and, among others, the neo-Nazi organisation Vanguard America.

READ MORE: What is the alt-right and what does it stand for?

Online organising made the alt-right's success possible.

The key websites are: AltRight.com; the Occidental Dissent blog; the neo-Nazi Daily Stormer website; Radix Journal; the Counter-Currents website and the Right Stuff blog, among others.

The alt-right has many connections to groups in Europe, many of which predate the movement.

Some prominent figures within the alt-right are: Daily Stormer's Andrew Anglin; the Right Stuff's Mike Peinovich; Identity Evropa's Nathan Damigo; former Ku Klux Klan leader David Duke; Traditional Worker Party's Matthew Heimbach and Swedish businessman Daniel Friberg.

Alt-light

The alt-light is a term used to describe a comparably moderate group of far-right figures, organisations and websites.

Unlike the alt-right's call for a white ethnostate, the alt-light promotes a hardline version of American nationalism and often eschews the openly racist and white supremacist politics advocated by the alt-right. Much of the alt-light's positions are predicated on support for President Trump.

The most prominent website on the alt-light is Breitbart News, a far-right blog headed by Steve Bannon, who briefly served as Trump's top strategist. Another increasingly important alt-light publication is Rebel Media, a Canada-based website founded by right-wing media figure Ezra Levant.

Some of the most important personalities within the alt-light include: provocateur Milo Yiannopoulos; media personality Gavin McInnes; journalist and activist Lauren Southern; social media figure Mike Cernovich; media personality Alex Jones and conspiracy theorist Jack Prosobiec.

Yiannopoulous used to be the technology editor at Breitbart News, but he was fired after public uproar over comments he made defending pedophilia. Recently, he has hosted anti-Muslim rallies and "free speech" events. He often verbally attacks immigrants, trans people and feminists.

McInnes co-founded Vice Media and later left the company in 2008. Most recently, he hosted a Rebel Media online programme. He also founded the Proud Boys, a far-right group that describes itself as "Western chauvinist" and opposes feminism. The Proud Boys often brag about seeking out physical confrontations with anti-fascists, known as Antifa.

READ MORE: How the US anti-Muslim marches were defeated

There are also several conspiracy theory websites that fall within the sphere of the alt-light. The most well-known is InfoWars, hosted by Alex Jones. In 2015, Trump, who was a presidential candidate at the time, appeared on InfoWars and was interviewed by Jones.

Many alt-light groups argue against the alt-right, while others have participated in the same rallies and events as alt-rightists.

Militia groups

Most militia organisations describe themselves as "patriot" groups. The largest and most active of the militia groups are the Oath Keepers and the Three Percenters. Member of these groups often attend rallies armed with assault rifles and wearing bullet proof vests.

While it is difficult to know the exact number of people involved in these organisations, the Oath Keepers claims to have tens of thousands of members nationwide.

Historically, the militias were considered anti-government. They claimed that they were defending the US Constitution from politicians who were seeking to impose unconstitutional and authoritarian rule on the country. However, most of them have been vocal supporters of the Trump administration.

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Militia organisations often show up to protests held by groups they view as political opponents - Black Lives Matter and anti-fascists, among others - where they claim to be maintaining order by carrying weapons.

Common among groups such as the Oath Keepers are former and current law enforcement officers and military members.

Although these groups claim to reject racism and white supremacy, they have been present at many rallies and events alongside alt-rightists. On April 15, militia members came to Berkeley, California, where they rallied with alt-right groups and participated in street brawls against Antifa and other counter-protesters.

Conflicts between alt-right and alt-light

The alt-right and the alt-light have always shared several political positions and had common opponents. Both camps oppose the Democratic Party, Black Lives Matter, Antifa, undocumented immigrants and their advocates, and others.

Some alt-light leaders used to be open supporters of the alt-right, and others have migrated from the alt-light to the more hardline alt-right.

Recent months have seen increasing tensions between the alt-right and the alt-light, and their divisions have grown more defined.

In Houston, Texas, these divisions spilled over into a physical confrontation.

On June 10, Oath Keepers demanded that William Fears, a 30-year-old construction worker and alt-right activist, leave the rally. Angered by the Fears' racist posters and refusal to leave, one Oath Keeper member put Fears in a chokehold. The incident was filmed and widely publicised online.

READ MORE: US anti-fascists - 'We can make racists afraid again'

Later that month, on June 25, the divide played out again when the two groups held competing "free speech" rallies on the same day in Washington, DC.

During this event, the alt-right's Richard Spencer openly criticised his more moderate counterparts. "They're liars, they're con artists, they're freaks," he told reporters of the alt-light. "The alt-right will be better when we just cut away these people who are going to weigh us down."

Charlottesville as pivotal moment

On August 12, alt-rightists attended "Unite the Right", a rally in Charlottesville, Virginia to protest against the removal of a statue of Confederate icon General Robert E Lee.

During the event, 20-year-old James Alex Fields rammed his car into a counter-protest, killing 32-year-old anti-racist Heather Heyer.

The alt-light joined the chorus of public condemnation as Fields was charged with second-degree murder.

However, critics have noted that Jason Kessler, a former journalist who had recently joined the alt-light Proud Boys group, organised the rally.

The Proud Boys condemned the rally.

Several other alt-light figures denounced the events in Charlottesville, while alt-rightists celebrated them.

Speaking to Vice News, alt-right member Chris Cantwell said that Heyer's killing was justified. The day after the rally, the neo-Nazi Daily Stormer described Heyer as a "fat, childless 32-year-old slut".

READ MORE: How neo-Nazis 'burn crosses' from behind keyboards

On the other hand, Gavin McInnes, then at Rebel Media, denounced James Alex Fields, who was charged with Heyer's murder, as a "domestic terrorist".

In response to the Charlottesville violence, alt-light Twitter personality Mike Cernovich decried the alt-right.

"That's all the alt-right stands for, is white nationalism," he told The Atlantic at the time. "They are now indistinguishable. Worse than that, they are now associated with domestic terrorism."