Can you spot the baffling letter in this headline that 72% of people miss?

Most people do not even know that two forms of the letter exist. Photo / 123rf

What is in 'everything' yet is rarely spotted? The answer, somewhat surprisingly, is the letter 'g'.

Despite seeing it millions of times, a new study has found that 72 per cent of people cannot identify the lowercase 'looptail g' - the form of the consonant where the lower arc is completed to form an oval - like in this story.

The oversight is all the more striking because that particular form of the letter is the one used in most novels, newspapers and email messages and most people will use it every day, the Daily Telegraph reports.

Participants were shown four versions and asked to pick out the correct one. Photo / Telegraph

According to US researchers at Johns Hopkins, in Baltimore, the phenomenon occurs because schoolchildren do not learn to write the letter's looptail, meaning few commit it to memory or even notice it on a printed page.

In fact most people do not even know that two forms of the letter exist.

Study lead author Professor Michael McCloskey, a cognitive scientist at Johns Hopkins, said: "We think that if we look at something enough, especially if we have to pay attention to its shape as we do during reading, then we would know what it looks like, but our results suggest that's not always the case.

"What we think may be happening here is that we learn the shapes of most letters in part because we have to write them in school. Looptail 'g' is something we're never taught to write, so we may not learn its shape as well."

Unlike most letters 'g' has two lowercase print versions, an open-tailed one that looks like a loop with a fish hook hanging from it, and the closed-tailed version.

To test people's awareness of both versions, researchers conducted a three-part experiment. First they asked people if they knew there were two kinds. Just two people out of 38 did.

Author Kimberly Wong, a junior undergraduate at Johns Hopkins, said: "We would say, 'they're are two forms of 'g'. Can you write them? And people would look at us and just stare for a moment because they had no idea.

"Once you really nudged them on, insisting there were two types of 'g' some would still insist there was no second one."

This particular form of the letter 'g' is the one used in most novels, newspapers and email messages and most people will use it every day.

Next the team asked 16 different participants to silently read a paragraph containing 14 looptail 'g's paying attention to the characters. They were then asked to write the 'g' that they had seen. Despite just seeing the letter a moment ago, half wrote the wrong version.

In a final experiment 25 people were asked to pick out the correct looptail 'g' in a multiple choice test with four options, such as the looptail reversed. Just seven succeeded.

"They don't entirely know what this letter looks like, even though they can read it," said co-author Gali Ellenblum, a graduate student in cognitive science at Johns Hopkins. "This is not true of letters in general."

The experiments suggest knowledge of letters can suffer when people do not write them by hand. And as people write less and become more dependent on electronic devices, this could impact how we learn to read, according to the researchers.

The research was published in the Journal of Experimental Psychology, Human Perception & Performance.