# Why can't we feed datetime to Linear Regression and how does toordinal() different from any other integer datatype?

I'm working with dates for the first time. First I knew I had to convert it to timestamps which gave me the values in "datetime64" values. But then I came to know that Linear Regression from sklearn does not accept datetime as dtype for regression. Why is that? Also, after executing df.date = df.date.map(datetime.toordinal) I saw that the datatype for the column is "int64". How does the sklearn LinearRegression know it is not any random int64 dataand a datetime data (considering the fact that I got the needed model after plotting)?