Street Art It Is...

Let me talk about Street Art in my own words here, I'll try and explain you all that I've read about Street art from different books and websites.

Graffiti and street art are generally described as any form of unsanctioned art that occurs in a public or privately owned space. Typically the terms are used synonymously, but works belonging to each term possess qualities that represent differences in style, motivation, and purpose.
Street Art can be considered any art seen in the street. Literally any kind of Art!
For Example:

This is 3D Street Art, Which looks like its 3D but

  actually its just a 2 Dimensional painting.

This is a sand sculpture, which is also considered

as Street Art.

This is called street installation. Clearly a lot

of material is used in making of this, and not

only paint. This is not graffiti, but this is 

Street Art.

So like this there are many more types of art that are considered to be the Street Art but are no Graffiti. This can be the major difference between Street Art and Graffiti. Also Graffiti is a part of Street Art. And there are different types of Graffiti which come under types of Street Art.

(Author - Aman Banwait)