Do you know what this is?
No, it's not a drunken number 8, it is, in fact, the symbol for infinity.
Last night's Horizon (BBC 2, 9.00pm) dealt with the concept of infinity - and what a concept it is!
Infinity (symbolically represented by ∞) is a concept in mathematics and philosophy that refers to a quantity without bound or end. (The word comes from the Latin infinitas, meaning 'unboundedness'.) People have developed various ideas throughout history about the nature of infinity. In mathematics, infinity is defined in the context of set theory.
In mathematics, 'infinity' is often used in contexts where it is treated as if it were a number (i.e., it counts or measures things: 'an infinite number of terms'), even though it is not really a number. Oh and there's more than one kind of infinity.
Confused yet? Me too.
So you might want to sit back and watch Horizon's attempt to unravel the mysteries of the infinite. It's is older than time, bigger than the universe and stranger than fiction, and it's on BBC iPlayer here.