Reading the Card Explains the Card.

Stop getting butt hurt when someone says this to you, the phrase literally answers all of your questions by asking you to re-examine the card you're asking questions about.

See that card above? Someone asked, "What is this card's color identy?" I'm sure you have eyes and can see the blue, black and red mana symbols on the card right? That means this card has a three color identy, despite it being an artifact. I do not know why people have such a hard time with color identy, or say really how any card actually opporates within the confines of the game, as though these things are somehow not readily unstood by just comprehending what words mean and associating them with the things that they interact with. When someone tells you to read the card, they're not just being an ass hole, they're trying to get you to think. So put your big non-binary pants on and do what everyone else has down while playing magic; fucking read.