Background material on recombination
(Note that for the following, I am specifically recommending the videos that I link to here; others on the topic, including followup videos by the same creators, are not necessarily accurate and should be viewed at your own risk. In particular, pay close attention to the use and misuse of genetics terms [e.g. "allele," "linked"] in videos not specified here.)
This video does a good job of explaining recombination.
In the next recommended video, the instructor uses the term "gene" in his demonstration - the term "locus" would be more general (loci do not need to contain genes; loci are still linked or unlinked). When watching the video, think about when you would use the term "locus." Also think about where the term "haplotype" fits into this lecture.
A general note: Loci are linked or unlinked (alleles are not linked or unlinked). It doesn't matter which alleles any given individual's genotypes or haplotypes contains - the amount of recombination you expect to observe between loci does not depend on that.