A Computerized World

Chapter 1 discussed many aspects of computers that apply to the average, non-computer science major. I use several forms of data storage myself every day. My laptop computer has a total hard drive storage capacity of 232 GB, which equates to about 250,057,060,352 bytes (like our textbook mentioned, GB are not measured according to the regular decimal system, but rather uses the number 1024, rather than 1000, as a multiplier; that's shown in my own hard drive, since the total number of bits does not equal 232,000,000,000).

I use four other forms of data storage almost everyday. My family has a video camera and transfers the videos we take to DVD's, a type of magnetic storage. CD's (yes, I still use CD's in the 21st century) are another type of mass magnetic storage I use to store audio songs. Recently I bought an external harddrive which I use to backup all of the important files (documents, music, pictures, etc.) in case my computer's hard drive crashes (which it has already once in the past...). Lastly, I use a flash drive every Thursday at my computer science lab - the computers we use in class are frequently reconfigured, so we have to save our work to a flash drive so that it does not get overwritten; we can then use that flash drive to work on our material on any computer on campus.

Bit patterns (using only the symbols 0 and 1) are used by computers to represent everything shown on a computer - text, numeric values, images, even sound. ASCII and Unicode are the two main programs used to represent letters, positive integers, and other symbols. When I traveled to Spain two summers ago, I got to see a computer keyboard featuring Spanish symbols (n with a tilde, vowels with accents, etc.). I now know that those symbols are probably made representable through a code like Unicode. Pictures are another thing I use daily that are configured using bits. The pixels that make up images contain a color that is determined based on three bytes: one red, one green, and one blue. The color and shade all depend on the different combinations of bits in RGB encoding.

I've used a calculator for most of my education thus far, and one of the properties this chapter taught us that pertains directly to calculators is the concept of overflow. Overflow happens when two negative bit strings produce a positive bit string (or vice versa) or when the addition of two bit strings produces a string that is bigger than the allowed byte size. In calculators, overflow happens with the latter - numbers that are too large (the bit string cannot be represented) cannot be displayed and are replaced with the message of "Overflow."