Recombination occurs during meiois, and involves randomly cutting and rejoining of lengths of homologous DNA. There is always at least one recombination event per chromosome pair so that a chromosome in the haploid gamete's genome is a hybrid of the parental chromosomal pair.
A haplotype is the pattern of variants observed at a set of polymorphisms along a section of a chromosome in a gamete. It can be used to infer where a recombination event fell on the chromosome (along with knowledge of the parental haplotypes).
