Structure of Social Security Numbers. A Social Security Number (SSN) consists of nine digits, commonly written as three fields separated by hyphens: AAA-GG-SSSS. The first three-digit field is called the area number. The central, two-digit field is called the group number. The final, four-digit field is called the serial number.
Fabrication, is the building of something brand new, that's never been seen before, or invented. Manufacturing, is the duplication of something on a mass scale. Generally, the way it works is, you fabricate something that you need, then manufacture what you fabricate. A good example is, a car company decides to design a brand new car from the ground up.
Modern steel fabrication involves the manufacture of large and often complex welded assemblies of rolled steel products. High temperature processes are used to make the steel products, to form the components and to join them together, so dimensional variation resulting from distortion is inherent and unavoidable.