Explain the relationship between single nucleotide polymorphisms ("snps") and restriction fragment length polymorphisms ("rflps")? how are they caused and why do they matter?

SNPs are DNA sequence variations that occur when a single nucleotide in the genome is altered. In order for an alteration to be considered an SNP, it has to be present in at least 1% of the population. RFLPs is one of the first techniques used to study the genetic variation of a population and it is based on the restriction enzymes that cut DNA on specific sites. The sequences produced by these cuts, are then studied.
They matter because they are used to detect differences in the DNA of a population and study the genetic variation.