When Ridley Scott directed the movie Alien he needed a decent tagline for it. What the marketing team went with was a simple sentence that also works out to be scientifically correct as well. It was “In space, no one can hear you scream”. Leaving aside the whole crew begin killed by a xenomorphic personality scenario this is very true because space is a vacuum. There is literally nothing in space or at least there is virtually nothing to sustain anything living in it. However this lack of matter certainly has its uses as we shall see. For example we create vacuum’s in our life for use in a vacuum conveyor and companies such as https://www.aptech.uk.com/pneumatic-conveying-systems/vacuum-conveying can provide this. It is also used for most packaging creation in retail products and away from the commercial sector we use the vacuum cleaner in our homes plus creating very bright lightbulbs. Imagine how hard life would be without that lot!
A vacuum is a void or a vacant space. Naturally there is a Latin word for this and it is vacuus meaning void. Apart from being a cracking word to play in Scrabble (as long as you know you haven’t got the Q and on the odd occasion you get both the U’s) this is where it comes from. If you want to impress people when you’re watching Star Wars or Star Trek then say, “Ah, I see that the Death Star/Enterprise is in vacuo again”. This refers, in Latin again, when an object is in a total Vacuum. So, when they ask you what you’re on about when you say it now you can answer them.
There has been some debate in the past whether vacuums actually exist. The Greeks wrestled with the problem philosophically before Evangelista Torricelli took full advantage of the Renaissance period and nailed one of the first labs created vacuum’s in 1643. The only trouble is that whilst it could be proved that there was no oxygen in the tube scientists have come to accept that a vacuum containing absolutely nothing at all whatsoever is pretty much impossible, even in Space. You can try and take out all the matter that you like but there will still be something knocking around in the tube. These are things like gamma and cosmic rays plus natural fluctuations in the vacuum itself. How empty it is confirms the quality of the vacuum from a partial one to a free one. Space, for example, is as close to the free total vacuum as you are going to get, whereas the one for your Hoover is not.