These are commonly used by the alt-right to promote their belief in white supremacy and wish to rid Western nations of non-white citizens. Professor Greg Barton, an expert on terrorism from Deakin University, said that racist "shitposting" is common across the internet, and is a way for people to connect and gain attention. "The thing about social media is that it’s social. You want some feedback, you want people to like your stuff whether it's Instagram or Facebook," he said. "Shitposting is all about getting your profile up, getting a response and the more ironic and funny you can be the more you get." Tarrant’s brutal act of terrorism has already inspired hundreds of memes.

Loading A board on 8Chan call "Brenton Tarrant's Memetastic Warfare Thread", shows pictures from Tarrant’s live stream made up to look like scenes from the video games Minecraft, Call of Duty and Fortnite. Some posts copy mainstream meme formats. One shows a reclining woman next to the words "Women think men want" and below a picture of Tarrant entering the mosque, gun raised, next to the words "What men really want". Professor Barton said that this kind of extreme dark humour is an expression of the hyper-masculinity that fuels extremist groups. "Hyper-masculinity is an exaggerated desire to be seen to be tough and to be recognised as the alpha and to get respect ... Alt-right real-world communities often involved a fight club culture and a lot of real-world violence," he said.

"The online equivalent is to provoke, to bully to dominate and intimidate … it’s called toxic masculinity for good reason." Professor Barton says that the number of Australians in these online communities is likely in the thousands. "Nationally there would be several thousand people that police would be particularly concerned about, in the midst of thousands more that don't justify any surveillance resources," he said. "We know that with terrorism, in general, there is no standard profile. But generally, we are looking at lost boys. Young men that are struggling with masculinity." The use of online forums is by no means exclusive to the alt-right.

Islamic State and other jihadist groups are known to connect and recruit online, however, Professor Barton says these online cultures differed in some significant ways. "Broadly it’s the same stuff, but the difference is the alt-right tends to be heavier on irony and dark humour. Heavier on just general 'shitposting' and heavier on trolling compared to debate" he said. While jihadist groups tend to seek superiority through religious justification and perceived piety, Professor Barton said the alt-right show dominance by being as outrageous and darkly ironic as possible. "The alt-right is much more quick to go into this dark justification of violence." Much like the "Incel", or involuntary celibate, online community these forums have developed their own vocabulary. They refer to "Chad's" to reference strong, traditionally masculine white men and call people like Tarrant "accelerationists", referring to speeding up the rate of social change.

References to Nazi imagery and racially derogatory terms are also a common feature. The 8Chan site is made up of a maze of images boards, messages threads and anonymous posts. Professor Barton says that young men often find these sites when they are already on the road to radicalisation. "What gets them there is the more public stuff," he said.