A quark is a generic type of physical particle that forms one of the two basic constituents of matter, the other being the lepton. Various species of quarks combine in specific ways to form protons and neutrons, in each case taking exactly three quarks to make the particle in question.
There are six different types of quark, usually known as flavors: up, down, charm, strange, top, and bottom.

Strange
A world devoid of a girl like her
Would be Strange indeed
For when we have a girl like her
She’s all a boy would need

Charm
The world will reel and wobble
From my lover’s Charm
And when you see her beauty
You’d have her on your arm

Top
When it comes to class and alacrity
She is at the Top
Her meteor is quickly rising
And I don’t think that it’ll stop

Bottom
When it comes to selfish pride and haste
You know she hasn’t got them
For when you look upon that list
She’s always at the Bottom

Up
Life has its Ups and downs
There is no life without them
But with a girl like her around
Only ups you’ll find then

Down
She is joy unconstrained
Floating on a cloud of mirth
But when she sees me coming
She settles Down to earth