FREQUENTLY, I am surprised by the number of friends and relatives who, when they reach a certain age, find themselves drawn to a singular pastime. Some are a bit defensive about it. Others are triumphant. Their common passion is a slight looking thing – the ukulele.

That moderately comical-looking musical instrument, with its high twanging sound, is now the instrument of choice when older people decide it is time to take up music again.

Yes, we know the gags: why are people frightened when someone comes into a bank carrying a ukulele case? They think he’s carrying a ukulele and might be about to use it.

But we prefer the comment of George Harrison, of Beatles fame, who succinctly said: “A lot of music can suck you dry of humour – but not the ukulele.”

Last week I found out more at the Rio Cafe in Hyndland Street, Glasgow, a quirky bar where lovers of craft beers can happily co-exist with Partick locals out for a fry-up meal, singers waiting for their turn on open mic nights, and once every three or four weeks, an open invitation for ukulele players to join together for a jaunty recital.

But why the ukulele? Older readers may vaguely recall the black-and-white films of a buck-toothed George Formby leaning against lamp-posts singing slightly risque songs while strumming a ukulele. Then there was Tiger Tim who squashed the instrument’s attempts at credibility by his falsetto-induced rendition of tulip tip-toeing.

That, though, is in the past. Put simply, there are far fewer strings attached to playing the ukulele. And by that I mean a guitar has six strings usually, while a ukulele has four.

It means twisting your fingers on the neck of the instrument to form chords is simple compared to a guitar. Some notes only need one finger on a string. Give yourself half-an-hour with a ukulele player showing you what to do, or following some short tutorials on YouTube, and you can happily strum along to many a tune.

Players tell me that the thought of going back to their school-learned cello or clarinet would be too daunting. Picking up a ukulele is a joy in comparison. And as the Rio Cafe shows, it doesn’t have to be a solitary pursuit.

Throughout Scotland there are bars having ukulele nights regularly. Nor is it just for the older clientele. The evening at the Rio had many young people. Some were there for the first time and had only recently bought their instrument – a reasonable one will only set you back about thirty quid.

Playing in a group, they can join in when they can, or simply just sing along if they reach a note they are unfamiliar with. Organiser of the Rio night, Carol Jamnejad tells me she has tried many instruments, but she just really liked the ukulele – the name is Hawaiian, after a small stringed instrument was taken to the islands by a Portuguese sailor, and its popularity soared until it became ubiquitous on the islands.

As Carol explained: “It’s really accessible. It’s still difficult to play well, but easy to play when you accompany songs. It’s never boring. That’s what I like about it.”

We’ve just finished a rendition of The Wild Rover. A group having dinner further down the bar stand up to leave. I feared the ukulele playing was driving them away, but they sing along as they walk to the door, and stop to applaud as they leave, perhaps wishing to convey that it is an appointment elsewhere that is engineering their egress and not the music.

Nor is this a traditional folky night. We go from Wild Rover to Amy Winehouse’s Valerie, perhaps sung in a more cheerful manner than poor Amy did. But that’s the thing with the ukulele, it cheers you up.

Amongst the players at the Rio is Mark Daniels, who this night favours an eight-stringed uke that is clearly more difficult to play but gives you a fuller sound. So Mark is one of the more accomplished players there, but that’s the thing about the uke – no one shows off.

He tells me: “It’s not competitive. The ukulele is not pretentious. I’ve known gatherings of guitar players where there is someone who wants to show off which can be off-putting for people who want to join in but have never been before.

“The ukulele is not like that. Nobody should be scared of it. You are never going to be judged by fellow ukulele players.”

He too emphasises its accessibility and says: “It’s easy to pick up and get a sound out of it. The basic chords are really straightforward.”

By now a member of the collective is handing out lists of songs to Rio customers sitting nearby who can make requests. Carol and friends have brought along music for the players. Essentially, most of the songs are reduced to four or five chords. Even if you think your fingers are like a bunch of bananas you should be able to master the changes in finger position quite quickly.

The Rio gathering is a loose affair with different folk turning up each time it is advertised. There are more organised groups, such as the West of Scotland Ukulele Players, who have worked out the instrumentation of more than 500 songs for the uke.

Enthusiastic players like Carol often take their instruments to care homes and hospitals to entertain residents.

The playing at the Rio lasts for two hours, and you can see that those who brought their instruments are having a jolly time. Singing and playing a ukulele lifts the spirits.

As George Harrison once wrote in the introduction to a ukulele songbook: “Everybody should have and play a uke. It’s so simple to carry with you and it is one instrument you can’t play and not laugh.”

And you don’t have to sing about cleaning windows.