- Introduction
- Understanding Vector and Raster Graphics
- Understanding Paths
- Creating Rectangles and Ellipses
- Creating Polygons and Stars
- Creating Line Segments
- Creating Arcs and Spirals
- Creating Grids
- Understanding Selections
- Using the Selection Tool
- Using the Direct Selection Tool
- Using the Lasso Tool
- Using the Magic Wand Tool
- Selecting and Grouping
- Selecting Similar Objects
- Saving and Editing Selections
- Moving Objects
- Duplicating Objects
- Aligning and Distributing Objects
- Transforming Objects
- Using the Free Transform Tool
- Rotating and Scaling Objects
- Reflecting and Shearing Objects
- Applying Multiple Transformations
- Reshaping Objects with Envelopes
Understanding Vector and Raster Graphics
Illustrator is an application that gives you great control over vector graphics, which include vector shapes and vector objects. Vector graphics are created using mathematical shapes, not pixels, and that’s why vector shapes are considered resolution-independent. For example, if you enlarge a vector image to 100 times its original size, Illustrator merely changes the mathematical formulas to reflect the new size, and since vector shapes are constructed of mathematical data instead of pixels, file sizes are extremely small.
Raster graphics, such as bitmaps and photographs, are images creating using individual pixels that identify one piece of color information. The reason raster images are considered resolution-dependent is that once the image is created or scanned, any enlargement of the image forces Illustrator to enlarge and average the existing color information in the document. This process, called interpolation, is what causes enlarged raster images to become blurred, or pixelated.