This video from Vox is pretty helpful when talking to friends or family potentially confused by the incredible variety in vaccines that appear to be available, but really aren't.
When and where the studies on vaccine effectiveness and what metrics are being tracked/shared massively impact the idea of effectiveness that one may come to after hearing quick reports in the media, or listening to people who like to participate in boat parades.
If someone is worried about side-effects, this video is good to share with them:
