ORCID (Open Researcher & Contributor ID) is a non-profit registry of permanent researcher identifiers. Most scholars have run into trouble at one time or another when searching for articles by an author with a common name, who published under different variants of their name (including in other languages), or who changed their name. Sometimes even subtle changes, like whether you include a middle initial, can impact the ease with which scholars can find your work. ORCID aims to solve the name ambiguity problem by providing researchers with a unique ID (like a social security number for your scholarship).
ORCID's services are publisher-neutral and intended for scholars in any discipline, type of organization, or geographic location. You can include many forms of scholarship, from multimedia projects to patents to translations.
Here are a just a few reasons to create an ORCID profile:
This Nature blog post explores the benefits of ORCID in more detail.