Clean air is odourless, tasteless, invisible, and pretty boring, but we'd have considerable trouble living without it, since we breathe it.
Air is, of course, useful for many other things beyond breathing. It's a useful medium for the convection of heat and for burning things in. This is because of the level of oxygen content. The world would be a cold place above its surface without air.
We get many of the things we need for manufacturing from the air. The nitrogen and inert (noble) gases are quite good at stopping oxidation (burning) during welding, and of course, the oxygen is useful if we need to burn something. The Argon that we can seperate from the air is used in light bulbs to prevent the burning of the filament, and liquid nitrogen is quite useful for freezing things. Beyond that, air allows soundwaves to travel through the space around us into our ears, and so allows us to communicate verbally. Air can be used to inflate things that we need to be large when used, but tightly packed for travel, and the comfortable ride in cars due to the pressurised tyres comes courtesy of the air.
So there it is - air. Unless you're in space, it's likely you're surrounded by it.