There are at least five roles that falls under the PR umbrella.
Social Media Manager
In the event you are new to contracting a PR firm or a Publicist; here is some detailed information to help you in knowing just what you may need. Make sure you have a budget to accommodate each role.
A publicist is usually the role people think of when they are referring to a PR professional. Publicists work closely with clients to help develop and implement their brand strategy.
Also, they are accountable for discovering publicity, promotions, and determining the best ways for clients to market their brands to the press and to their customers. Many publicists also use celebrities or people known in the community to market their brands.
A copywriter is in charge of writing promotional and marketing materials. This may be from PR announcements to blogs and it is usually done relative to a strategy created by the PR team. Copywriters are also in charge of maintaining a solid brand and identification across multiple platforms in real time.
more in related article