"DNA is the recipe in a cookbook that can't leave your Grandma's house (nucleus). You want it so you copy (transcribe) the instructions onto a post-it to take home with you (mRNA). It's still just a code; you can't eat the post-it, and it looks slightly different than the format in the actual cookbook but contains the same information. You then take this into your kitchen (the ribosome) and then as the cook (tRNA) you read (or translate) the words and then assemble the ingredients. So you know that egg means those oval things in the fridge just like tRNA knows that AUG (we call the words codons) means the amino acid methionine. Assemble the right ingredients and you have your food (chocolate cake!) or protein (red hair)."