Is a vacuum always a vacuum?
When we hear the word vacuum the first thing we usually think of is a vacuum cleaner. Scientifically, a vacuum is a space that is devoid of matter, including air. Vacuums create suction because matter, especially air, wants to fill spaces that are empty. The first scientific (literally, in a test tube) vacuum was created in 1640 by Evangelista Torricelli (who wanted to test Galileo's theories about air and matter).
Ironically, however, the first "vacuum" cleaners did not use vacuums at all. Instead, they were blowers! They were literally made of bellows that someone squeezed to blow dirt out of the way. Needless to say, they were not especially effective at controlling dust.
The first vacuum cleaner to use suction was not invented until 1908. Over 250 years after the first man-made vacuum was created, an asthmatic janitor named James Murray Spangler, got tired of breathing in dust as he swept carpets at his job. He used an electric fan (ever notice that fans suck in air from the back?) attached to a pillow case and a broom stick to create a vacuum cleaner that is suprisingly like the modern day vacuums we use now (although -- what would he have thought of Roomba?).