The appearance of the opener was preceded by the invention of what is required to open, that is, canned food. Napoleon's army needed long-term storage products, so the French government promised a reward to anyone who found a solution to the problem. Then pastry chef Nicola Appert proposed the preservation technology, which the mankind uses to this day.

But since only glass jars were used at that time, their fragility caused considerable inconvenience. British industrial engineer Brian Dunkin was the first to develop the process of canning in tin-coated steel tin cans. This made it possible to save food perfectly, but opening it was quite inconvenient. Interestingly, the producers of canned food themselves recommended using a hammer and chisel for this purpose, which they even wrote on the label of their products. At that time, the tin can was significantly different from the present one. Its walls were very thick, and it often weighed more than its contents. Therefore, at the beginning of the XIX century, Napoleon's soldiers had to resort to extreme measures, they opened cans with a bayonet or shot them.

later, cans became lighter and thin-walled, and in 1858 the first can opener was patented in america. it had two blades: a sharp straight one with a limiter for piercing the can and a curved one for cutting the lid. then this design was improved, and there was a classic knife for opening canned food with a handle in the form of a bull's head. instances of this type can be found today. after some time, the so-called "cutting wheel"was invented to open cans. It was a bottle opener that operated on the principle of a compass, when one leg was stuck in the middle of the jar, and the other with the help of a sharp wheel cut a hole in it.

In 1925, progress took a step further, the company from San Francisco was able to improve the previous design of the device. To do this, a gear was placed in the lower part, which served as a feed wheel. This made it possible to clearly fix the rim of the can between the gear and the opening blade, ensuring smooth cutting without slipping. Even later, magnets for fixing the can and an electric drive were added to the opening device, but the general principle has not changed until now. to date, the evolution of can knives or can openers has gone even further. There is a huge selection of these devices, among which there are mechanical, automatic, universal, electric. Each of them has its own advantages and is used depending on the need. so, for example, the mechanical model is often used in the home kitchen, the universal one is convenient to take with you on a hike or on a picnic. Automatic is often used in catering establishments, where you need to open a lot of cans and do it quickly. If you want to have devices for all occasions, you can buy a set. Let's look at the devices in more detail.

The mechanical opener is a device that moves the cutting roller in a circle with the help of a rotating lever and thus opens the jar. When using such a can opener, no sharp edges remain on the tin. Some instances are equipped with magnets that allow you to remove the lid without touching it with your hands.