An individual's genotype is its entire collection of gene variations (i.e., alleles). The term "genotype" usually refers to how the individual's variations make it a unique member of its species. The observable manifestation of these genetic differences is called the individual's phenotype.
For example, consider the Punnett square below, which shows the four possibilities for the inheritance of the Mendelian factor corresponding to flower color (purple vs. white) in pea plants. A plant may have the different genotype "BB" (homozygous dominant) or "Bb" (heterozygous), but in both cases it will display purple flowers as its phenotype.