The G-series lens uses a high-speed, high-precision contrast-detection AF driven by the sensor at up to 240 fps, while the S-series camera uses a Phase Hybrid autofocus system.
The listings specify a 3.0-inch rear screen and indicate no viewfinder is included for the model(s) shown.
The listings identify the Micro Four Thirds mount standard for the G-series/Micro Four Thirds-compatible lenses.