Many people (including my close family) are not aware of the various useful screenshots macOS and its apps provide. 
Often they are very surprised when I show them handy shortcuts like the one for deleting an entire line, or the one that starts a screen recording.You can, of course, look up keyboard shortcuts in the menus and there are lots of shortcut cheat sheets on the internet. But I found none of them really appealing to nontechnical people.So, last year, I designed my own shortcut cheat sheet. But instead of putting it all on a full-size letter sheet, I had the idea to print mini cheat sheets for various apps and topics in the size of business cards. That way, you can easily have one or two cards on your desk for the shortcuts you really need. I had these printed on cardboard paper and started giving them away to friends and family.I think knowing your shortcuts really makes your life easier. Everybody should have their set of cheat sheet cards on their desk! But, of course, I can’t send a deck of cards to everybody.As an app developer, I thought: What better way is there for us than creating an app with the shortcut cards?The result is “Shortcards”, which is both a website and an app. You can simply look up and learn shortcuts on <a href="https:&#x2F;&#x2F;shortcards.app" rel="nofollow">https:&#x2F;&#x2F;shortcards.app</a>And with the free native app, you get a handy reference directly on your Mac or iPhone. In the app, you can quickly search for shortcuts, conveniently filter by topic, and mark your most-used or high-priority cards as favorites for instant access.
It includes shortcuts for basic macOS system commands, Finder navigation, and text editing.

Show HN: Shortcards – Mac keyboard shortcut cheatsheets for friends and family