What does it mean when u send a message its blue but it doesnt say delievered?

Question

I was just curious because the message didn't turn green, it is blue but just doesn't say delievered.

Answer 1

Green is SMS.
Blue is iMessage.

Delivered & Read messages depend on whether the recipient has ' Read Receipts' switched on or off.
You cannot force a read receipt if the person to whom you sent has them switched off.

On iPhone/Pad - Settings > Messages > Send Read Receipts.
On Mac - Messages > Preferences > iMessage > Send Read Receipts.