The most basic tool for every artist and doodler! The black of a standard Sharpie has it’s very own beauty.
The more one uses it, the more one learns how to play with the sharp point and to vary the line… if you are comfortable mangling the tip a little, the softness can become almost brush-like.
For quick and dirty drawings, I love the Sharpie. It doesn’t bleed, nor smudge easily, and you can make it do both those things with a little saliva or rubbing alcohol to make additional effects.
If you’re courageous, the rubbing alcohol can also separate the base pigments in the ink and create halo effects… play with it like watercolors and see.
The permanence of the ink is nice on most substrates but will wash out in time on cloth, if it’s washed with detergents. I have yet to experiment with sun-bleaching.
Sharpie offers a ton of colors now, and they also have a variety of tips, if you want to experiment.