The "Doomsday Clock" says we are 90 seconds away from midnight,

after atomic scientists kept the predicted point of the world's annihilation as they did last year - as close to midnight as ever before.

But what does that really mean?

And where did the concept of the "Doomsday Clock" even come from?

The "Doomsday Clock" is a symbolic timepiece showing how close the world is to ending.

Midnight marks the theoretical point of annihilation.

Every year scientists move the hands of the clock closer to or further away from midnight

based on their reading of existential threats at that time.

Cambridge University's expert on existential threat Paul Ingram explains.

"It emerged at the beginning of the Cold War to give a sense of the urgency to achieve nuclear disarmament and to climb out of the abyss that we were facing in the early 1950s. And in more recent times, it has taken on climate change and emerging disruptive technology to give a sense of the the risks, the catastrophic risks that we face as a planet largely through our own deliberate activities."

Albert Einstein was among a group of atomic scientists who created the clock back in 1947.

These days, a Chicago-based NGO called the Bulletin of the Atomic Scientists updates the time annually.

A board of scientists and other experts in nuclear technology and climate science, including 13 Nobel laureates, discuss world events and determine where to place the hands of the clock each year.

When the clock first started ticking, more than 75 years ago, it sat at seven minutes to midnight.

In 1991, the clock was the furthest it has ever been from doomsday - at 17 minutes.

That was the time when the Cold War ended and the United States and Soviet Union signed the Strategic Arms

Reduction Treaty that substantially reduced both countries' nuclear weapons arsenals.

"If we maintain an addiction to competition and to conflict as a way of managing our social interactions and our interactions with ecosystems, we will perish. I think as the threats go get larger and that we become more aware and we understand them better, there is hope, I think, but we do change our practices and the way we we think and approach these things.''