Calendar Event Color

Hello   @jandrews

From my testing on my Mac, it appears that the solid blue events are events that you have scheduled, or events that you are going to. Solid white events are on your calendar which you have not responded to (i.e. you've been invited to an event but have yet to respond). Events that have lines through them are events you have said 'maybe' to, and events that are crossed out you have declined. You can right click the event to mark yes/no/maybe which will change the color accordingly. 

I hope this helps and please make sure to mark the solution as accepted if this information is what you needed.

Thank you,

Jake

I am not finding the same other than the events with lines through were responded to as tentative.  Al others have been accepted.