logo type: youtube
The YouTube logo is simple, bold and iconic. It uses the familiar play button symbol that had become associated with YouTube even before it was part of their logo. YouTube's target audience is just about anyone, since it contains many millions of videos aimed at a wide range of people across the world.
alphagram: xbox
The Xbox logo is sleek and modern. It looks like a futuristic white orb splitting open, as well as containing the letter X which is closely associated with the Xbox. Their target audience is gamers, so the futuristic and modern logo ties in with the technology of the brand.
abstract: pepsi
The Pepsi logo is simple, bright and very recognizable. It is abstract, because it's a colorful globe and not a picture of anything in particular. However, it's based of the logo Pepsi used during WWII, which was the bottle cap with the colors red, white and blue to show support of the war. Pepsi's target audience is anyone drinking pop and their logo is good because it's easy to remember and very recognizable.
The twitter logo, a lot like Pepsi, is simple and so recognizable it doesn't need any words/letters for people to know what it represents. The bird picture ties in to 'tweets', as well as giving a quick and simple feel. Twitter's audience is people looking to share on an easy to use and quick social media site, and its logo accurately gives that feel.
pictogram: twitter
combination: pinterest
The Pinterest logo contains an alphagram (the letter P in a red circle) and logotype (the name Pinterest). It's artistic and bright, which matches their reputation. Pinterest is (primarily) used as a place for artists to save pictures and projects so they can look at them later and get ideas, so the artistic script works well.
This is a small study of examples of the various types of logo out there, as well as an analysis of how effective they are at reaching their intended audience. It helped me learn more about what makes a good, effective logo.