PCM redirects here. For other uses, see PCM (disambiguation). Pulse-code modulation (PCM) is a method used to digitally represent sampled analog signals. It is the standard form of digital audio in computers, compact discs, digital telephony and other digital audio applications. In a PCM stream, the amplitude of the analog signal is sampled regularly at uniform intervals, and each sample is quantized to the nearest value within a range of digital steps.
1 As well as MLA, APA papers are also double-spaced with 1-inch margins on each side. 2  APA guidelines recommend you to use readable and clear font, such as Times New Roman, 12 pt.  The main distinction of APA style is a ârunning headâ at the top of each page.
For an in-depth example of how an APA-style paper should look like, check out this Sample APA Paper for Students Interested in Learning APA Style 6th Editionhttp://my.ilstu.edu/~jhkahn/APAsample.pdf by Dr. Jeff Kahn from the University of Illinois.