The history of the motor car is one of continuous innovation, with incredibly clever people relentlessly inventing new technologies to make cars safer, perhaps faster and generally better.
We're talking inventions such as seatbelts, fuel injection, anti-lock brakes, airbags and power steering - and the little arrow on your fuel gauge that tells you which side of the car the filler is on.
Okay, that last innovation isn't quite like the others. It didn't require countless hours of research, development, engineering and testing: it's just a sticker. But that simple innovation, dreamed up by Ford designer Jim Moylan in the 1980s, has surely made life immeasurably easier for countless motorists.
Moylan was filling up a company car on a rainy day and initially pulled up on the forecourt with the pump on the wrong side for the fuel cap. Suitably annoyed, he came up with a solution.
He suggested it to his bosses, and in 1989 the arrow was introduced on the Ford Escort and Mercury Tracer. These days, you'll struggle to find a fuel gauge that doesn't have one.
Because it's one of those 'hidden in plain sight' innovations, there's also a pleasing element of 'if you know, you know' and genuine delight when you watch someone learn about it for the first time.
Soon after my niece passed her driving test, for my first outing as a passenger we went to fill up her car. As we approached the fuel station she mentioned she didn't know which side the filler was on, and being able to let her in on the not-quite-a-secret was a moment of pure joy.
The brilliance of the now ubiquitous fuel gauge arrow is its simplicity. Cars are incredibly - and increasingly - complex things, and much of the technology that underpins them is staggeringly advanced. But the best solution to a problem will always be the simplest one. And here's a problem solved with a remarkably simple-and cheap-bit of lateral thinking.
But I worry we may be going backwards. Because while almost every fuel gauge now has an arrow, I've noticed only a few electric cars feature one to tell you which side the charging port is on. Which seems remiss, given how much variance there is in the location of them.
At a time when charging an EV is still a frustration for many, anything that can make it as simple as possible should be welcomed. So a plea to all car makers: when working on your lovely new digital driver displays for your fancy EVs, please spare just a few pixels for an arrow pointing to the side that's home to the charging port.
It won't cost anything, but it will make life just a little bit easier for your customers.
