OBL is “Out Bound Links” — these are links from your web site to other web sites.
IBL is “In Bound Links” — these are links from other web sites to your web site.
Inbound links are also referred to as “backlinks”.
Inbound links are very important in SEO (Search Engine Optimization) because inbound links raise your Page Rank (PR), which in turn raises your SERPS.
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