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computing system computer hardware, software and data which interact to solve problems computer hardware the physical elements of a computing system layers of a computing system: outside to inside communications, applications, operating systems, programming, hardware, information abstraction mental model that removes complex elements abacus 16th century bc blaise pascal mechanical device jacquard's loom punched card charles babbage analytical engine ada lovelace first programmer, introduced concept of loop alan turning turning machine hardware first generation 1951-1959 vacuum tubes, magnetic drum, punched cards (input, output), card readers/magnetic tape drivers hardware second generation 1959-1965 transistor, magnetic cores, magnetic disks hardware third generation 1965-1971 integrated circuits, transistors, terminal hardware fourth generation 1971-? large scale integration, very large scale integration, pcs, work stations, laptops parallel computing interconnected central processing and or memory units SIMD single instruction multiple data stream MIMD multiple instruction multiple data stream networking connecting computers to share resources, ethernet, arpanet, lan, man, wan first generation software 1951-1959 machine language, assembly languages and translators programmers of the first generation application programmers and system programmers second generation software 1959-1965 high level languages, compilers software third generation 1965-1971 systems software, time sharing, three types of users: application and systems programmers, general public software fourth generation 1971-1989 structured programming, new application software was developed fifth generation 1990-present object oriented design, world wide web, internet, three types of users natural numbers 0 to infinity negative numbers less than zero integer a natural number, negative numbers and zero rational number any number that can be expressed as a fraction of two numbers base specifies the number of digits used in the number system and also the value of digit positions positional notation a system of expressing numbers in which the digits are arranged in succession, the position of each digit has a place value, and the number is equal to the sum of the products of each digit by its place value binary numbers base 2 number system, contains digits 0 and 1 octal numbers base 8 number system, contains digits 0-7 hexadecimal numbers base 16 number system, contains digits 0-9 and a-f computers are... multimedia devices dealing with a vast array of information categories multimedia several different media types computers store, present, and help us modify many different types of data numbers, text, audio, images and graphics, video, stored in binary digits data compression reducing the amount of space needed to store a piece of data networks have... bandwidth restrictions bandwidth the number of bits or bytes that can be sent from one place to another over a fixed amount of time compression ratio the size of the compressed data divided by the size of uncompressed data, compression techniques can be either lossless or lossy lossless compression no loss of information when original information is retrieved from compressed information lossy compression some info is lost in the process analog data continuous representation of data digital data discreet representation of data digitize process of breaking down continuous info into discrete pieces analog signal continually fluctuates up and down digital signal has only two states, a high or low all electronic signals.. degrade as they move down the line, voltage fluctuates due to environmental effects pulse code modulation digital signal jumps sharply between two extremes number overflow a situation where a calculated value does not fit the number of bits reserved for it radix point the point that separates whole part from fractional part in a real number ASCII stands for american standard code for information interchange ASCII beginning info originally used seven bits to represent each character, allowing 128 characters, 8th bit was used to check transmission errors ASCII now info extended to represent each character with 8 bits, allowing 256 characters UNICODE 16 bits to represent each character different types of text compression keyword, run length and huffman encoding keyword encoding replacing regularly used words with a single character disadvantages of keyword encoding characters used to replace words cannot be used in the original text, different symbols for capitalized words run length encoding replacing a long series of a repeated character with a count of the repetition huffman encoding uses variable length binary strings to represent characters, so that frequently used characters are assigned smaller binary strings color depth amount of data that is used to represent a color resolution number of pixels used to represent a picture raster graphics format the storage of information on a pixel by pixel basis bitmap format supports 24bit truecolor gif format each image is made up of only 256 colors jpeg format averages color hues over short distances png format like gif but achieves greater compression with wider range of color depths a terminal is a computer with its own cpu, memory, and input output devices system programmers write programs for other programmers what does rgb mean red green blue video typically uses lossy compression what component did the transistor replace vacuum tubes one byte is equal to 8 bits in the formula for encoding a negative number in ten's complement, what does k represent the number of fixed values/digits what is an integrated circuit a combination of gates what tool converts a high level language into assembly language compiler