Because some database providers tried to solve the problem of mulitple authors with the same name before ORCID was developed, you should know about Reseacher ID (Web of Science) and Scopus Author ID, especially if you are publishing in the sciences or medicine.
ResearcherID is a unique identifier to enable researchers to manage their publication lists, track their times cited counts and h-index, identify potential collaborators and avoid author misidentification. In addition, ResearcherID information integrates with the Web of Knowledge and is ORCID compliant.
If your publications are generally indexed by Web of Science, you should probably create a basic ResearcherID account as well as an ORCID. It's easy to transfer information between the two profiles, including the list of publications from Web of Science. By having a ResearcherID, you can review variants of your author name to collect all of your publications together in Web of Science for inclusion in ORCID.
Scopus Author ID is another identifier used specifically by the Scopus database and has many of the same features as the ResearcherID in that it helps manage publication lists and citations.
You can request a ResearcherID from the homepage of the Web of Knowledge in the menu bar
Alternatively, you can request a ResearcherID
Go to http://www.researcherid.com/SelfRegistration.action and request a registration link using your name and email.
You do not need to register for a Scopus Author ID; if you have a paper indexed in their database, you are automatically assigned a Scopus Author ID. Use the free lookup tool to find your Scopus Author ID.