Form is the choice of which type of art you want to do: two-dimensional, three-dimensional. Two-dimensional will be mostly painting; three-dimensional will be a statute, sculpting, etc. It is possible to have a two-dimensional painting that has three-dimensional build that makes it pop-up more. However, it’s a still a two-dimensional painting. Two-dimensional can also be photography, mixed media (e.g., painting with oil/acrylic), or materials like metal, wood, fabric, clay, etc. Going back to painting, when it comes to form it can be on canvas, wood, glass, etc.
Function revolves around how we use art. In most cases, painted art is used to decorate our environment, whether it is our home or office. However, sometimes art is a means to convey a visual message to the viewer.
Texture is obvious in the world of sculpting. With painting, however, texture is only achieved via the brush strokes, depending on what type of material you are using. For example, when you’re working with watercolors, it’s very hard to see the brush strokes. However, when you use oils, this is one of the easiest ways to create texture. You can actually transition from smooth to rough quite easily. Oil and acrylics will produce the most texture.
