I have a dataframe with some "NaT" values in a datetime column. What does that mean? project status completed 0 windows done 2025-08-20 1 doors done 2025-08-21 2 hvac delayed NaT I checked the docs page pandas.NaT, but it just says "alias of NaT", which doesn't seem to make sense. I found plenty of SO questions, but I didn't see one that actually explains what NaT is. E.g. How do I check if a specific item in pandas series is NaT This is meant to be a canonical question with a self-answer. I'm not genuinely asking for myself, just want to put this out there since the docs page is lacking, and someone asked this question in earnest here: "What are NaT? All of the time values should be datetime objects." Continue reading...
