A degree or certificate from an accredited trade school is usually considered essential for a graphic design position. After a career history has been established, though, the graphic designer's experience and number of years in the business are considered the primary qualifications. A portfolio, which is the primary method for demonstrating these qualifications, is usually required to be shown at job interviews, and is constantly developed throughout a designer's career. One can obtain an AAS, BA, BFA, BCA, MFA or an MPhil / PhD in graphic design. Degree programs available vary depending upon the institution, although typical U.S. graphic design jobs require at least some form of degree. Current graphic designer jobs demand proficiency in one or more graphic design software programs. A common software package used in the graphic design industry is Adobe Creative Suite. This software package contains the three main programs used by graphic designers, which are Photoshop, Illustrator and InDesign. Photoshop, InDesign, and Illustrator are the industry standard applications for many graphic design positions. Another example of a common software package is CorelDraw Graphics Suite. Outside the graphic design industry, many people use Microsoft Word or Microsoft Publisher to create a layout or design. However, depending on the job at hand, most designers create the layout in either InDesign, CorelDRAW or QuarkXPress. Specifically, the designer will type or import the text in the layout program, also importing the graphics and images they created in Photoshop or Illustrator. There are a couple of reasons a designer builds a layout in this fashion: Files going to press are generally printed at 300 dots per inch. As a result, the file size can become very large, depending upon the photos and graphics used in it. By using a layout program and linking these graphics and images (but not saving all of them in the file itself), the wor