Texture refers to surface. Everything that has a surface also has texture. There are two kind of texture: tactile and visual texture.
Texture range from smooth like a mirror and rough like mountain. All surfaces have texture rather it’s rough or smooth. Different texture can affect interest in different ways. Texture can make an image more interesting it is not a strong enough element to be useful for organizing a composition. Value and color contrasts are more efficient at that. (2002 James T. Saw)
Tactile means touch. Tactile texture is the actual (3D) feel of a surface. The texture needs to either be felt, or seen with light raking across its surface to make the texture visible. Most painters use this texture to give their painting a lively look. Vincent Van Gogh is famous for the technique called impasto. Some painters use sand to their painting to give it that more that tactile texture. (2002 James T. Saw)
Visual texture refers to the illusion of the surface’s texture. It is what tactile texture looks like (on a 2D surface). No matter how rough the objects might look, the surface of the photo is smooth and flat. Both types are important to the designer, but in 2D art, the illusion of texture is used more than tactile texture. Visual texture is always a factor in a composition because everything has a surface and hence a texture. (2002 James T. Saw)
A pattern is a repeated pattern that repeats itself over and over. You see patterns in swirls designs, checker design and flower and so far. When you a design that has the same pattern over and over that is a pattern design. It can also be called an illusion design because it also has a repeated design. Some of other example you might see pattern in is furniture, picture and clothes etc. they all have patterns in them....