The iPod Shuffle has always been a more compact model. None of them have had screens but only something along the lines of a click wheel and place to insert headphones.
1st generation
Release Date: January 11, 2005
Storage: 512MB, 1GB
Battery: 12 hours of battery life
Features: no screen
2nd generATION
3RD GENERATION
4TH GENERATION
Release Date: September 12, 2006
Storage: 1GB, 2GB
Battery: 12 hours of audio battery
Features: 4 color options, smaller clip, aluminum casing
Release Date: March 11, 2009
Storage: 2GB, 4GB
Battery: 10 hours of audio battery
Features: smaller design, 2 colors, Voiceover featured