There are several types of coffee grind, usually referred to by the name of the equipment e.g. 'plunger grind', 'espresso grind'. The key difference is the size of the ground coffee 'particle'. Here's where it can get tricky. If the particles are too large for the type of equipment, the hot water won't be able to release all of the flavours, resulting in a weak, acidic coffee. If the particles are too small, you'll get a burnt, bitter taste, and end up with grounds in the cup. So if you're grinding beans at home, invest in a good grinder i.e. a burr grinder. Otherwise, play it safe and use a coffee that has been specifically ground for your equipment.
Espresso Or Stove Top Grind:
The finest of the grinds, with a powdery texture. This fine texture means the espresso machine can draw out all of the delicate flavours and oils in just 20-30 seconds, giving espresso its trademark rich, full flavour.
Plunger and Filter Grind:
A coarser grind. The medium sized particles allow the coffee to brew for 4 minutes without turning bitter and prevent the grounds from passing through the plunger or filter mesh. This size of grind is also suitable for Chemex.