Lecture Notes

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• Layer naming
• Save
• Save As
• Save a Copy
• Save for Web

• Table
• Flat file
• Relational database
• Distributed
• Examples: DB2, Access, and database products from Oracle, Sybase, and Computer Associates.

• During and when complete with any document produced from an application program, if one would like to re-open it later, it must be saved.
• Before saving, one must decide what the file is to be named.
• Care should be taken as to what it is titled, as well as where it is being saved. If this is not done, one may have trouble locating it in the future.
• At the end of each title, the will be the file extension, such as .psd (Photoshop), .jpg (jpeg file format), .tif (tiff file format), .dwg, (AutoCAD), and .doc (word document) for example. (The "period" separating the title from the extension is called the delimiter.
• Note: When saving a Photoshop file, for example, the type of file it is saved as can be very important. If you wish to save all the layers you have created, the extension must be .psd. If it is saved as a .jpg, the layers on the Photoshop file will be lost, with the exception of the background. To avoid this, if you are done editing the file, flatten the image, and then you will be able to save the file as a .jpg.
• If you would like to save the file for the web, Photoshop offers a feature, Save for Web, which optimizes the image to be transferred more quickly on web browsers.
• Some important features to keep in mind when working with graphic files:
• Dithering-deals with colors, and as they relate to screens.
• This describes what happens when a document contains more colors then the screen can display; or when the screen can display more colors then the document has included in it.
• Aliasing-converting the curves of an image into something, which a screen can more easily display. Referred to as the "zaggies".
• Anti-Aliasing-tries to smooth out edges, to reduce the "zaggies".
• Graphics can be separated into two types:
• 2-D graphics: bitmap, raster graphic, and vector graphics.
• 3-D graphics: vector graphics.
• Vector graphics deal with the description of a line.
• Boundary model versus solid model.
• Boundary model
• Zero dimensional elements (point or node).
• 1 dimensional elements (line).
• 2 dimensional elements (plane).
• 3 dimensional elements (although element appears solid, it is truly hollow.
• Solid model
• 0,1,2,and 3 dimensional objects, with the exception that they are solid.

• Introduction of databases
• Incredibly important to computing.
• Can be thought of as a table, with rows and columns.
• The simplest databases have just one table.
• These are called Flat Files.
• When there are 2 or more databases that refer to one and another.
• This is an example of a relational database.