It's no secret that Donald Trump is a prolific Twitter user and has one of the most followed accounts on the platform.

And this presents a golden opportunity for those who are quick and savvy enough.

Known as "Trump responders", there is a community of people who race to get the top reply to a Trump tweet.

When someone clicks on a Trump tweet, the top spot is coveted real estate that brings exposure to potentially millions of people.

Loading...

As popular US podcaster Alex Goldman puts it: "A Trump responder is a person who essentially responds to every Trump tweet in order to raise their own profile.

"Not just responds to every Trump tweet, they try to be first."

Take a glance through Mr Trump's Twitter feed and it's pretty quickly apparent that there are a handful of recurring names.

Just who are these people and how do they get the top reply?

How the top reply is decided

The top reply spot on a Trump tweet is seen as prime real estate. ( Twitter )

Twitter doesn't detail exactly how its algorithm for replies works but there are a range of factors.

Speed certainly plays a part but doesn't seem to be the definitive factor.

A blue verified tick on your account helps, as does it seems the amount of people engaging with your reply.

Twitter also prioritises the replies of people you follow, so different people may see different responses, and considers whether the original tweet author has replied.

Despite a crackdown on bots, there's likely also to be competition from those exploiting the system through automation.

Ed Krassenstein and Brian Krassenstein

Brian Krassenstein and his brother Ed are regularly replying to Trump tweets. ( Twitter )

The Krassenstein brothers are two of the biggest anti-Trump tweeters whose accounts have a combined 1.5 million followers.

They run a website called the Hill Reporter which they describe as an independently owned liberal news publisher.

It's not exactly clear how the two rose to such Twitter prominence, but they say they are there "to fact-check and counter the false narrative that the President appears to be propagating to his 56 million+ followers daily".

Mr Trump did for a time block the brothers from viewing and responding to his tweets.

The Krassensteins have also been accused of running Ponzi schemes, which they say is not true, and were once raided by US federal authorities, but no charges were laid.

Jacob Wohl and David Wohl

Jacob Wahl and his father are big Donald Trump supporters. ( Twitter )

Jacob Wohl is a conspiracy theorist and Trump supporter who, along with his father David, is often among the first in on Trump tweet replies.

Jacob, 21, made some headlines late last year for his involvement in a bizarre plot to discredit Robert Mueller.

He calls himself a "political and corporate intel consultant" and, despite his age, said he was an experienced hedge fund manager before being permanently banned from futures trading by US authorities.

His father is a lawyer and prolific tweeter, and says he was a campaign worker for Mr Trump.

Eugene Gu

Eugene Gu was part of a group that once sued Donald Trump. ( Twitter )

Eugene Gu is a doctor who was once part of a group of people who sued Mr Trump, and won, for blocking them on Twitter.

He's quick to hit back at Mr Trump's social media statements and usually doesn't contain himself to just the one tweet in reply.

Dr Gu researches fetal tissue transplants and was once subpoenaed to appear before a US House committee regarding this kind of work.

QAnon

QAnon has more than 100,000 followers on Twitter. ( Twitter )

QAnon is a pro-Trump conspiracy theory that has gathered steam in recent times and aims to "expose the deep state with factual information".

For those into conspiracy theories, searching around the internet about what these guys are into could keep you busy for days.

The main QAnon account has more than 100,000 followers and its supporters are often seen at Mr Trump's rallies.

A quick flick through the replies of Trump tweets and you'll often find @WeAreOne_Q featured prominently.