Save systems A save file is a serialized snapshot of game state that survives restarts. The hard parts aren't writing bytes — they're choosing what to save, writing it so a crash mid-save can't corrupt it, and reading old saves after you ship a patch. Get those three right and the rest is plumbing. When to use - Use to persist progress: player stats, inventory, world flags, settings, positions — across sessions and game updates. - Use to design save slots, quicksave/autosave, and crash-safe writes. - Use when old save files break after a content/code change (versioning & migration). When not…