Genotype is an organism’s full hereditary information i.e., what is in their DNA which is what is selectively passed down in various proportions from its ancestors. The genotype is the genetic code in an organisms cells. This genetic code contains the characteristics and traits that our birds possess.
Phenotype is the observable and physical expression of those genes (i.e., the Genotype). The phenotype is the actual observed and exhibited behaviour and traits.
The traits we may look for and value in our racing pigeons include such things as being a good trapper, quick orientation, speed, endurance, resistance to disease, e.g., the bird being a good producer and/or an excellent racer.
This is where it gets interesting as additional things contribute to the outward expression of the Genotype i.e. the phenotype.