Question..What is this thing..sex?

Well the dictionary describes it as

1.	either the male or female division of a species, esp. as differentiated with reference to the reproductive functions.

2.	the sum of the structural and functional differences by which the male and female are distinguished, or the phenomena or behavior dependent on these differences.

We describe it as Fucking..straight sweaty, limbs bending, breathing hard..etc. But do we really understand this "art"? Let's talk about it..