The most common brush shapes are:

round
flats
filberts
mops
fans
liners

The types of fiber art brushes are made of and their qualities:

There are so many different shapes it is impossible to show here, but below are some examples of the paint brushes available.

Natural Hair Art Brushes
Kolinsky Sable hair comes from the Northern areas of Russia. It is the finest and most expensive hair used in brush making and while it is made into brushes for all mediums, it is particularly good for Watercolor paints. It is an elastic soft hair that forms a beautiful shape with a long, pointed tip.	Squirrel hair is very soft and pliable with a long pointed tip. It can hold a great deal of liquid and is very absorbent so is particularly suitable for use with watercolor paint, gouache and tempera.
Pure Red Sable has been the soft hair brush of choice for many years. One myth that has developed is that you cannot use these brushes with acrylic paints. Sable brushes work well with acrylic paint but the problem is in the care and cleaning. The key is to clean your brushes often and well – before the paint dries and they will be your friend for many years.	Bristles are very resilient and have "flags" or split ends at the tips to hold lots of heavy paint. Bristle brushes are ideally suited for heavy bodied oil and acrylic paints.
Synthetic Art Brushes Fortunately in our hi-tech world they have developed a synthetic "hair" that have almost the same qualities as natural hair brushes but at a more affordable price. Made with the latest synthetic fibers, these paint brushes have excellent color carrying capacity and have fine points that hold their shape. .. and did I mention they were cheaper! -great if you are on a budget.
White Synthetic Art Brushes Most every brush supplier will have a white synthetic line of paint brushes. They have a Sable-like softness so make them ideal for smooth stroking and blending.	Orange Synthetic Art Brushes are the latest wonder of hi-tech brush making. This new fiber feels and responds just like Sable (so say the manufacturers). Even loaded with paint they have a strong firm point. Because of their softness, this series is ideal for glazing.

Paint brushes are an investment, and you want to get the most for your money you possibly can. If you care for it properly, a good brush will serve you for many years. Here are a few ways you can protect your investment, and avoid having to replace your brushes before they’ve reached their life expectancy.

• Clean your brushes as soon as you finish painting. Paint of any type, even water-based paint, should never be allowed to dry in a brush. If needed, you can use a formulated brush cleaner to remove paint from hair. Then use soap (like shampoo) and warm water, rinse thoroughly and reshape.

• While painting with your brushes and between use, soak your brushes in water or solvent to keep the paint from drying in the hair. A brush holder that will hold the brushes suspended in the liquid, without crushing the hair, is an excellent investment.

• Brushes should dry in an upright position to protect the shape. Allow your brushes to dry thoroughly before storing them in a closed container. A storage container made just for brushes is ideal, but a tool box with a separate compartment for brushes will also work well. Don’t store your brushes in such a manner that the hair will be bent or have paints and other materials resting on top of them.

• Keep your brush handles dry. Even the finest brush handles will loosen and crack when left soaking. Fill your water or solvent container so that it just covers the brush head, and the handle doesn’t get wet.

• Don’t use watercolor brushes in acrylics or oils and expect them to deliver the same performance afterwards - they won’t.

• Don’t use expensive natural hair brushes on rough surfaces, including rough or textured canvas, or they will wear out very quickly. Synthetics are more suited to these surfaces, and less costly to replace..

• When you have a bit of time condition your Natural Hair brushes. Lard oil is inexpensive, found in any good hardware store and is just what a brush needs after weeks of painting on rough surfaces, and being cleaned with solvents.
Spread out a old towel or heavy rag, lay down your brushes with heads all pointing in one direction, then put a drop or two of oil on each brush head. Gently work the oil into the hair and wrap the brushes up in the towel (making sure brush heads aren’t bent). You can store for up to 2 weeks and when you unwrap the brushes, the oil should be fully absorbed. Wash brushes gently and they are ready to go.