The actual cake you bake is your phenotype. It's the physical expression of the recipe. It's what you see – the color, the taste, the size, etc. The phenotype is what the genotype produces.
So:
* Genotype: The genetic makeup of an organism. It's the complete set of genes an organism inherits from its parents. You can't see it directly, it's like the hidden instructions.
* Phenotype: The observable characteristics of an organism. This includes things like eye color, height, hair color, even things like disease susceptibility. This is what you *can* see and measure.
For example: You might have a genotype that codes for brown eyes (let's say "BB"), and your phenotype would be brown eyes. Someone else might have a genotype that codes for blue eyes ("bb"), and their phenotype would be blue eyes. Things get a little more complicated with combinations of genes, but this is the basic idea.