ORCID iDs are used by publishers, funders, associations and other organizations to make sure your work is correctly attributed to you, to unambiguously differentiate you from other scholars with the same name, and to streamline workflows such as submitting and reviewing journal articles, applying for funding, and more:
Globally unique, permanent identifier that stays with you for life, independent of name or institutional affiliation changes
You own your ORCID iD, not your employer or publisher