As a vector graphics program, the work flow of Illustrator is much different than that of photoshop, and will take a bit of working with to learn its value, something one understands and appreciates the more you work with it.
Photoshop, creates raster images (Simplified explination is individual pixels with x/y coordinates and a color value) that can be ‘erased’ one by one. This gives us very richly detailed and colored files that can be huge, and are not generally scalable without loss of resolution
Illustrator creates vector graphics ( defined points that are connected with color / stroke values etc. – think of a connect the dots type graphic that you color…)that do not have individual pixels that can be erased. This gives very crisp graphics that are compeltely scalable, very small file sizes with a reduction in overall details and number of colors displayed.
To remove a portion of a vector graphic you can ‘Select’ the points and delete, cut a line with the sissors tool, or use the pathfinder to knockout sections.
It would be recommended to checkout the Tutorials in the Help section, or better yet get one of the many books that will get you started.
The above explanations are very basic, but I hope they help!
keep at it…
Troy
troy@crossmediacorp.com
http://www.crossmediacorp.com