Most sold chair in history is one you’ve probably never paid much attention to

The most-sold chair in history is quite literally everywhere, with more than one billion units made since its invention.

That's one chair for every eight people on Earth.

But, despite its undeniable popularity across cultures and continents, you've probably never even noticed it.

The unassuming chair was never intended to be iconic but rather an efficient piece of furniture that was easy to make and cheap to buy, yet it has still made its way onto the New York Times' list of 'The 25 Most Defining Pieces of Furniture From the Last 100 Years.'

While its original source is unknown, a 1972 design by French engineer Henry Massonnet is often credited as its closest relative, although there's also a credible claim that Canadian designer D.C. Simpson created an even earlier version in 1946.

Regardless, neither design ever reached the dizzying heights of success of the Monobloc.

Made from one seamless piece of plastic, it doesn't require any screws, joints or extra materials, and can be manufactured in just under two minutes.

The iconic piece of garden furniture is also stackable, washable, light enough to carry with one hand and durable enough to withstand the elements.

And, it's cheap to produce - coming in at approximately $3.50 (£2.75) to make.

More than one billion units have been made of the most-sold chair in the world (Getty Stock Images)

The chair comes in an array of fun colours to suit anybody's taste and variations of the chair are available to buy online for a price so low that it barely registers as a purchase.

NYT hails the garden armchair's clever design and low production cost.

"To make a chair out of just one piece of material is something of a design Holy Grail, one that became more attainable around midcentury with advancements in plastics technology," it says, and describes it as 'immune to trend and cultish adoration.'

The Monobloc chair's design has been lauded for its low cost and durability (Getty Stock Images)

Yet, the Monobloc chair has been a controversial piece of furniture over the years.

It's been called disposable, ugly and unsustainable, with millions ending up in landfills and the thermoplastic polypropylene it's made from taking up to 30 years to break down.

Reaction to the popular chair on social media has been mixed.

After a post of the most-sold chair in history was shared on Instagram, one person wrote: "Love it. Reminds me so much of my German grandparents home."

Another called it 'an instant classic.'

But others weren't so convinced.

One user commented: "Not efficient not durable, just cheap. So by our country’s standards, perfect," while another said it was 'a pure design insult.'