Denotation means the literary definition of a word. To give an example, the denotation for “blue” is the color blue. For example: "The girl was blue." You mean the girl was quite literally the color blue.
For connotation, it is the emotional definition of a word. To give an example, the connotation for "blue" is the feeling sad. For example: "The girl was blue." You mean the girl was feeling sad or feeling down.
