All genes with sufficient sequence similarity to have evolved from a common ancestor anywhere in evolutionary time are , while are genes in different species that arose from the same gene in a very recent ancestor of the two species and arise by duplication events within the same species.

Homologs,Orthologs, Paralogs

Explanation:

Homologs are referred to as gene that form the basic of Organization. They are homologous protein with genes coding for it.

They have the same ancestor and similar base sequence.

Orthologs are genes that arise from the divergence of a gene into two. i.e two genes arising from splitting of a gene having a common ancestor

Paralogs are genes form when a gene is dulplicated. This duplication of gene gives rise to a paralog.