Professional directories are online or printed resources that list individuals or organizations within a specific profession or industry. These directories often include contact information, areas of expertise, and sometimes reviews or ratings, making it easier for users to find qualified professionals for their needs. Examples of professional directories include LinkedIn, Yelp, and Angie's List. These directories serve various purposes, such as helping job seekers connect with potential employers, allowing clients to find service providers, or enabling professionals to network with peers. They can be industry-specific, like medical directories for healthcare professionals, or more general, covering a wide range of fields.