Digital art has two main creation methods, bitmap/rastor, where you draw like on paper, and work with pixels.
http://graphicssoft.about.com/od/aboutg ... ctor_2.htmVector is very different, instead of working with squares of color (pixels) you work with manipulable objects, which can me shrunk or grown or morphed, without losing resolution. It's the the digital, 2D equivalent of Silly Putty.
Some explanations/tutorials of vectoring:
http://xerkylereizem.deviantart.com/art ... -101152146http://bellacielo.deviantart.com/art/In ... -105928484You can see the little points and lines that can be dragged around to change the shape of things!
Examples:
http://horizonpl.deviantart.com/art/Vec ... e-69142049http://s0h3illvii.deviantart.com/art/flOwer-163084979Some of my own vector art: (not super good as I don't have a lot of experience with it)
http://i.gyazo.com/4100bce49d243e0110080a3f6c9f6ab8.pnghttp://i.gyazo.com/47032ab220003ab879e3a7b12c863d46.pnghttp://i.gyazo.com/4c0ef7ef3a1d6a924382910b5bdb8429.png-----
Illistrator is a high-end, professional, expensive vector program.
Inkscape is free. I've never used this, but my friends swear by it.