A check-in is an [[Obsidian Entity|entity]] that associates one or more notes with a date and time. It represents, for example, a concrete time I visited a [[Place|place]]. Check-ins are part of my [[How I Use Obsidian#Journaling|journaling workflow]] as well as [[Using Obsidian as a Personal Atlas|my personal atlas]], since I like to have these atomic relations to be used with [[Obsidian Bases Plugin|Bases]].