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Module 2 Software Outline Software Copyrights and licensing Operating systems Software applications Word processors Spreadsheets Graphics Databases A Fast, Stupid Machine Computers: Perform arithmetic and comparison operations Follow precise instructions to perform an operation Execute instructions quickly and accurately Processing with Programs Software programs are: Instructions that tell the computer what to do and how to perform tasks Written using a programming language Stored in memory Designed to solve problems The Language of Computers Machine Language : numeric codes to represent data • 1’s and 0’s High-level language : fall between machine language and natural human language • C++, Java, Visual Basic Compilers are programs that translate high-level language into machine language Natural Languages include the languages spoken by humans • English, French Copyrights, Licensing and Ownership Copyrights and Ownership Copyright: a form of legal protection for the creator/owner of a specific program or piece of software. It grants certain exclusive rights such as the right to copy, to see and distribute, and the right to modify the software. Buying a copy of the software does not give you these rights! Commercial software is copyrighted so it cannot be legally duplicated for distribution Licensing License Agreement: A legal contract that defines how you may use the software purchased. You obtain the right to use the software within the boundaries defined by the license. You do not • become the copyright owner • gain the right to copy, share, or modify the software. Shareware and Freeware Shareware: Works on the “honour system” “Try-before-you-buy” • Often has limited features vs. a regular edition ($) • Install for free but send $ if you decide to continue using it Freeware: Freely available for anyone to use Author abandons all rights to the product Beware of malicious intents Open-Source Software Software that is freely distributed, along with its source code People are encouraged to modify its code, enhance it, debug it, distribute it Software evolves through input from any interested persons Becoming increasingly popular “copyleft” Operating Systems Operating Systems The OS “controls the show” by: Communicating with hardware components Allocating/accessing memory and HD space Multitasking Starting up and running other programs Managing data, programs, and hardware resources Coordinating network communication Starting up the computer (booting) Where does the Operating System live? Some computers store their operating system entirely in ROM (Read Only Memory) Other computers include only part of it in ROM The remaining system is loaded into memory (booting) Most of the time it works behind the scenes Operating Systems Some common OS: Windows (98, NT, XP, ME, 2000, etc.) • GUI Mac OS • GUI Unix • Text-based • Remains dominant operating system for Internet servers Linux • Text-based • Open-source, continues to be a work-in-progress User Interfaces: The human-machine connection Includes all parts that allow a user to interact with the computer Often, the user interface is thought to include only what the user sees on the screen • Character-based Interfaces MS-DOS, Unix • Graphical User Interfaces (GUI) • Mac OS, Windows Why WIMP Won Windows, Icons, Menus, and Pointing devices • They’re intuitive • They’re consistent • They’re forgiving • They’re protective • They’re flexible Word Processors Word Processors Initially modeled after typewriters 1964: IBM Selectric (magnetic tape) 1970: display screens 1980s: personal computers, WYSIWIG Word Processing process Entering and editing text Formatting and proof-reading Saving document to disk • As you enter text, it is displayed on the screen and stored in RAM. Save work often because RAM is not permanent memory. Printing the document Formatting Formatting refers to how the words look on a page Levels of Formatting Character / Text Line & Paragraph Entire Document Character formatting Font: Typeface is the style in which each symbol is drawn or formed (the kind of lettering used) • Serif fonts have serifs or fine lines at the ends (tails) • Sans-serif fonts have plainer, cleaner lines Font size is usually measured in “points”. • 72 pts = 1 inch tall Arial A Paragraph Formatting Formatting for paragraphs involve margin settings, line spacing, indents, tabs and justification. Document Formatting You can impact the appearance of an entire document through the following: Style sheets Headers and footers Multiple columns Table of Contents and Indexes Sectioning Conversion to HTML for web publishing Spell Checkers, Grammar & Style Checkers Spelling checkers compare words in your document with words in a disk-based dictionary. Words may be flagged; you make the decision to ignore or change the spelling. A grammar and style checker flags possible errors and makes suggestions. It spots the following: • • • • Spelling Errors of context Common grammatical errors Stylistic errors Spreadsheets Spreadsheets Initially modeled after accountant ledgers 1979: VisiCalc Dynamic rather than static like ledgers 2000: still using many of the same principles as 20 yrs ago Spreadsheets Worksheets: Columns and rows: Like sheets in a ledger. Can have many worksheets in a document Worksheets are divided into columns and rows. Columns are usually enumerated with letters, rows are numbered Cell A1 Cells: The intersecting of a column and row. Named after the specific column and row. This is called the “cell address”. Eg. A3 is the cell in column A, row 3. Cell C12 Types of Data Data that can be entered in a cell: Labels: text, like headings and notes Values: actual numerical values (including dates and times) Formulas: allow you to create instructions using math expressions and commands • start with a special character telling the computer to perform the following calculation. • Can reference other cells. E.g. =B4 + C1 would retrieve the values from cells B4 and C1, add them together, and display the result in the current cell. Spreadsheet Features Functions (e.g., SUM, AVG, SQRT) are used to automate complex calculations Automatic recalculation Any time a change is entered into the spreadsheet, all data related to the change automatically updates Macros let you store keystrokes and commands so they can be played back automatically Templates offer ready-to-use worksheets with labels and formulas already entered Graphing capabilities let you produce charts representing your data Spreadsheet Graphics: From Digits to Drawings 200 Bar charts (use if data falls into a few categories) 150 North West East 100 50 0 1st Qtr Pie charts (show relative proportions to the whole) 2nd Qtr 3rd Qtr 15% 20% 65% Line charts (show relationships or trends over time) 100 90 80 60 40 20 46.9 45.9 30.6 20.4 38.6 45 34.6 North West East 27.4 0 1st Qtr 2nd Qtr 3rd Qtr What If? Spreadsheets allow you to change numbers and instantly see the effects of those changes. “What if I enter this value?” Limited database capabilities Search for information Sort the data by a specific criteria Merge the data with a word processor Generate reports Graphics Graphics talk Pixels are tiny dots of white, black, or color that make up images on the screen. Palette of tools that mimic real-world painting tools and other tools unique to computers Color depth is the number of bits devoted to each pixel. 24 bits or 8 bits. Resolution is the density of the pixels. DPI: dots per inch. Bitmapped Graphics Images are a collection of pixels. The picture is mapped pixel-by-pixel Changes made by changing the color of individual pixels Object-Oriented Graphics Drawing software stores a picture as a collection of lines and shapes (called object-oriented or vector graphics). It remembers things like “there’s a blue circle at coordinates (100,200)” then, when it wants to display the image, it goes through all of its instructions and redraws the picture. Memory demands on storage not as high as bit-mapped images. Pixels vs. Objects Bit-mapped painting (pixels) gives you these advantages: More control over textures, shading and fine detail Appropriate for screen displays, simulating natural paint media and embellishing photographs Pixels vs. Objects Object-oriented drawing gives you these advantages: Better for creating printed graphs, charts, and illustrations Lines are cleaner and shapes are smoother Digital Image Processing: Photographic Editing by Computer Software that allows the user to manipulate photographs and other high-resolution images with tools such as Adobe Photoshop. Far more powerful than traditional photoretouching techniques. Can distort and combine photos as demonstrated in the tabloids Create fabricated images that show no evidence of tampering For example: http://www.alias.com/eng/etc/fakeorfoto/quiz. html Building a Photo Collage Take an image Combine it with other objects Make a statement Animation: Graphics in Time Each frame of computer-based animation is a computer-drawn picture and the computer displays those frames in rapid succession. Tweening-instead of drawing each frame by hand, an animator can create key frames and objects and use software to help fill in the gaps “Anything you can imagine can be done. If you can draw it, if you can describe it, we can do it. It’s just a matter of cost.” James Cameron, Filmmaker, ”King of the World” Desktop Video: Computers, Film, and TV Video editing software such as Adobe Premiere makes it easy to eliminate extraneous footage, combine clips from multiple takes, splice together scenes, create specific effects and other activities. Morphs are video clips in which one image metamorphoses into another. Data compression software and hardware are used to squeeze data out of movies so they can be stored in smaller spaces. It took three hours to render, or digitally paint in, the effects for each frame. 1200 processors One frame of the film converts to roughly 12 MB of storage space. One second of film takes up 24 frames. Databases The Electronic File Cabinet: Database Basics A Database is… a collection of information stored in an organized form on a computer Database software (DBMS) is… application software (like word processing and spreadsheet software) designed to maintain databases (collections of information) What Good Is a Database? An electronic database allows you to: store large quantities of information retrieve information quickly organize and reorganize information print and distribute information in a variety of ways Database Anatomy A database is a collection of one or more database files A file is a collection of related information (records) Database Anatomy A record is the information relating to one person, product, or event (one row in the table) A field is a discrete chunk of information in a record (one cell in the table) Database Anatomy The view is a display of the information in fields based on a particular layout of field data. Form View List View Database Operations These operations are used to manipulate the information in the database: • • • • • Import: Browse: Query: Sort: Report: receives data in the form of text files navigates through information finds records that match a specific criteria rearranges records (alpha or numerically) printout of an ordered list of records SQL Structured Query Language • Select * From Population Where Sex = M and Age > 18 and Age < 35 What Makes a Database Relational? A database is relational when files are related to each other, such as this Student ID field in the Student file. Database Trends Real-Time Computing Downsizing and Decentralizing Using a client/server approach Data Mining Allows instant access to information Allows technology to find valuable information Databases and the Web Information is available via a company’s Intranet and the Internet Database Trends Multimedia Databases Natural Language Databases Serve as an index for art, photographs, maps, video clips, and other media files Allows users to ask for data using the same language used to address humans Object-Oriented Databases Make database construction and usage more flexible Corresponding Textbook Readings – 121 P.130 – 152 P.156 – 166 P.178 – 198 P.210 – 235 P.100 To Know – Module 2 Keywords How do copyrights and licensing of software work? What do operating systems do? What are the main characteristics of Word processors Spreadsheets Graphics and Animations How do databases work?