Logo is a symbolic representation of your organization which is created on different software like photoshop,corel draw and flash ,there are many more way to get logo concepts like there are so many sites to http://www.logolaxy.com
check out the link below, there u can see the logo of isabel hospice logo and i really like this design as it carries only to smooth colors and a fine composition.
Well, take Mcdonalds for example. You know the big m sign??? well when you are looking for mcdonalds in the phone book or wherever, its easier to find the big m instead of the word mcdonalds in plain...