When the royals step out on official business, they know they'll be courting masses of attention.
So it's no wonder they are always on their best behaviour while out and about.
But while no-one really knows what goes on behind palace walls, there's often much speculation about the so-called rules and protocol they must adhere to.
However, the rumours aren't always true! Here we reveal the times that royals, including the Prince and Princess of Wales and even Meghan Markle, debunked some of these so-called rules that have either been relaxed or never really did exist...
Selfie ban
The royals are no strangers to having their photo taken - with photographers ready to capture their every move while out on duty.
But there used to be one type of snap they appeared to avoid, prompting speculation they weren't allowed to pose for selfies.
Although a ban on royals posing for selfies was not part of official protocol, several members of the Firm had previously revealed their dislike of the photos, including Prince William and the late Queen.
But fast-forward to recent months - and with most well-wishers turning up to royal events with their phones in hand - the likes of William and Kate have been seen throwing their arms around the public and smiling for photos with them.
Even King Charles and Queen Camilla have got involved - happily obliging for members of the public.
Nail polish rule
One long-rumoured rule that royal ladies were said to have adhered to was a ban on brightly-coloured nail polish.
It had been claimed that only clear varnish or nude or light pink tones are allowed to be worn on nails.
In fact, the only polish the late Queen was ever seen wearing in public was a very subtle pink shade.
However, last year, the Duchess of Edinburgh seemed to debunk the rule while on a four-day solo tour of New York.
During her tour, Sophie stunned in a number of striking outfits, including a black leather skirt and a stylish dress by Victoria Beckham.
And if you look closely enough, pictures showed her nails painted a chic shade of dark red, which goes directly against the supposed royal rule.
Meanwhile at Easter this year, Kate was also seen sporting a dark red colour on her nails.
No hugs
It was a long-held notion that whenever greeting royals, the public should only offer a handshake, bow or curtsy.
And while this rule might have existed in the past, royals including William and Kate have proved it seemingly doesn't still stand now.
Last year, William was pictured embracing 66-year-old William Burns, who was overcome with emotion on meeting the future King at an engagement in Glasgow.
Similarly, earlier this year, Kate was also seen hugging her former teacher after a surprise reunion with him.
It came as she and Prince William made their first official visit to Cornwall together since receiving special new titles - Duke and Duchess of Cornwall.
And after a tour of a museum, the royal couple were greeted by cheering crowds, with Kate surprised by Jim Embury, a former teacher from her prep school.
Kate said "Oh my goodness" and hugged Mr Embury, now a volunteer at the museum, before exclaiming: "I do recognise you."
Travel no-no
It was previously said that royal tradition dictates that those in direct line to the throne should never travel on a plane together.
It was believed that should the plane crash, the monarchy would lose key people near the top of the line of succession.
However, this rule has not been followed by William, who has flown many times in helicopters and planes with his eldest son and fellow future King, Prince George.
It's thought the tradition dates back to the early days of air travel when flights weren't deemed as safe.
However, in the years running up to her death, the late Queen relaxed the rule.
A royal spokesman said in 2014: "While there is no official rule on this, it is something that the Queen has the final say on."
Bare legs faux pas
When carrying out duties, royal women are often seen wearing tights if they are sporting a dress or a skirt.
And it became commonly thought that the late Queen had an unwritten rule about guests and family members wearing tights at royal events.
However, royal ladies including Kate and Meghan have been seen going without the hosiery at certain events.
And Marlene Koenig, royal expert and Royal Musings blog founder, previously told BAZAAR.com this the tights rule wasn't true
She said: "There are no rules for royal women regarding pantyhose.
"While most women (royal or commoner) wear pantyhose with suits or gowns for a good slim line, it is not required by any decree from the Queen."
Autograph ban
However, despite many of these so-called rules being debunked, there is one that definitely still stands - and it was confirmed by Kate just last week.
She made the admission during her visit to the Chelsea Flower Show, where she toured the show grounds with some curious school children.
At one point, Kate and the kids looked around the Royal Entomological Society's garden, where they tried to identify the bugs there and drew some sketches.
Keen to secure something to remember her by, some of the children asked the princess to sign her name on their drawings.
But according to The Telegraph, she told them: "My name's Catherine. I'm not allowed to write my signature, it's just one of those rules."
However, not wanting to leave the children empty-handed she drew some sketches for them - including one of a flower, another of a tree and one of a pond surrounded by some plants.
