“Glucose syrup” is what some in the English-speaking world call corn syrup. Indeed this incredibly thick and sticky stuff is corn syrup, just a rather special kind. In what way? It’s exceedingly low in moisture, which makes it handy for all sorts of confectionery work where you want to keep the finished product flexible without adding extra water to it. It also has a much cleaner taste than grocery store corn syrup because it has fewer of the thickening long-chain starch molecules in it.
Rarely does a baker use glucose syrup, save in caramels and fondants. The fascinating thing about it is that despite being nearly 100% glucose it doesn’t taste very sweet compared to conventional syrups, even though it’s made of the simplest of sugars and the general rule is that the simpler the sugar, the sweeter it tastes to humans. It does of course have every bit as many calories. Even more really, since most syrups are about 20% water. Just one of the quirks of the way our taste buds work. Curious indeed.