I don't use Twitter, but this sounds more confusing now. Stars are used throughout other services or systems for favoriting something such as bookmarks and if I

I don't use Twitter, but this sounds more confusing now. Stars are used throughout other services or systems for favoriting something such as bookmarks and if I "star it", I can revisit it in the future. But that means only I can see it. Hearts on Instagram are broadcasted to my followers, Facebook likes as well. Is this also the case on Twitter now? There's a difference between saving something for personal recollection and also broadcasting it.