Acrylic paints are water based and and can be purchased in a thick or thin format and and very fast drying making it great for painters who want to work quickly.
As Acrylic paint is water based it can be diluted with water, but becomes water resistant once it has dried. If watered down a lot or used with additives, acrylic paint can resemble watercolour paint and can be used with watercolour techniques. If used undiluted, or made thicker it has a closer resemblance to oil paint and can be used to create oil-painting like effects.
Acrylic paint can be used alone, or used with additives and mediums. You can use additives and mediums to change the properties of the acrylic paint. You can make it matte or gloss, thin it or thicken it, you can even buy several kinds of texture mediums such as glass bead gel to create unique effects on your painting.
Acrylic paint can be used on stretched canvas, canvas boards and acrylic paper. You can also use an acrylic gesso primer and paint on paper and other porus materials. Some additives can be used to enable you to use acrylics on other materials such as glass and fabric.