A contact role defines the part that a contact or person account plays in a specific account, case, contract, or opportunity. For example, Tom Jones might be the Decision Maker for the opportunity, and Mary Smith might be the Evaluator. You can assign a contact role to any contact or person account that affects your account, case, contract, or opportunity. Contacts and person accounts can have different contact roles on various accounts, cases, contracts, or opportunities.
The Contact Roles related list of an account, case, contract, or opportunity displays the roles that each contact or person account plays in that record. On person account detail pages, the Opportunity Contact Roles related list displays the opportunities on which the person account is listed in the Account Name field of the opportunity.