The difference between vector and raster graphics is the quality. In vector graphics, images are made up of connected points that form together to create an image. If you try to resize that image, it's no problem because the points just resize and fill in the space. However, raster graphics are made of pixels and that means that if and image is resized or modified, pixels will be lost, which will lead to tremendous loss of picture quality. Vector and raster graphics are similar in the fact that they both have parts that work together to create an image. They are used in graphic design based on their purposes. If you are drawing a cartoon or designing a logo, vector graphics in Illustrator is the program to go for. But, if you are simply editing a photo, raster graphics used in Photoshop is the obvious choice.
How is Adobe Illustrator similar to and different from Adobe Photoshop?
The previous question leads me neatly into the subject of the differences and similarities of Photoshop and Illustrator. Both have similar tools. Both have drawing capabilities. Both allow text graphics. And, with an experienced user, both can be used to design comics and logos. Get really experienced on both, though, and you'll notice that they are both different worlds. In Illustrator, your imagination for creation is not limited. You options of creating exactly the design you want to make are there when you need them. It is really easy once you get used to it and you can create what you imagine. On Photoshop, though, you are limited. Poor drawing tools, like lack of anchor points, limit the possibilities of your plans and designs. But Photoshop isn't meant to draw pictures. It is supposed to be used for photo editing, hence the name "Photoshop".
How are logos a form of visual communication for the business, organization, or product they represent?
Logos play a crucial role in representing your company or organization. Often, they are the first thing a person sees upon learning about you company, so it's actually their first impression. Have a logo too complicated and crowded, and then it just looks ugly and confusing. Have a logo too simple and meaningless and it will be useless. Have an elegant, simple logo which clearly represents your intent or products, and you'll be successful and your company will rise. Logos are one of the very things that point out what the company is like.