UID

A unique identifier (UID) is a character string, either numeric or alphanumeric, that is assigned to an individual item within a broader system. UIDs are special to each item, which makes it possible to access one specific item quickly and efficiently without needing to sift through a large number of similar items. UIDs can be generated randomly by an algorithm or manually by a human user.

How are UIDs used?

A UID can be used in a wide range of scenarios and disciplines. Most commonly, a website or application assigns a new UID when a new user registers for an account. Sometimes these UIDs are automatically generated and assigned without visibility to the end user, but usually the system uses the username provided during registration as the UID. This is why many registration forms will reject a proposed username if it’s already taken by another user.

UIDs can also be used to distinguish columns or fields in databases or spreadsheets. In relational databases specifically, UIDs are synonymous with primary keys, which are used to sort data by field.

Code sets in healthcare settings can be considered UIDs. Providers, insurers, and other healthcare professionals use these codes to identify various medical tests, diagnoses, procedures, treatments, and supplies. Unique identifiers are also frequently used to replace a patient’s name to streamline all related patient data and protect the patient’s privacy.

Examples of unique identifiers

The following list contains common examples of UIDs:

  • Serial numbers, which identify physical products
  • URLs, which identify web addresses
  • SSIDs, which identify wireless networks
  • GUIDs, which identify user accounts, documents, hardware, software, and other items in Windows applications
Kaiti Norton
Kaiti Norton is a Nashville-based Content Writer for TechnologyAdvice, a full-service B2B media company. She is passionate about helping brands build genuine connections with their customers through relatable, research-based content. When she's not writing about technology, she's sharing her musings about fashion, cats, books, and skincare on her blog.

Top Articles

The Complete List of 1500+ Common Text Abbreviations & Acronyms

From A3 to ZZZ we list 1,559 SMS, online chat, and text abbreviations to help you translate and understand today's texting lingo. Includes Top...

Windows Operating System History & Versions

The Windows operating system (Windows OS) refers to a family of operating systems developed by Microsoft Corporation. We look at the history of Windows...

How to Create a Website Shortcut on Your Desktop

Website Shortcut on Your Desktop reviewed by Web Webster   This Webopedia guide will show you how to create a website shortcut on your desktop using...

Generations of Computers (1st to 5th)

Reviewed by Web Webster Learn about each of the 5 generations of computers and major technology developments that have led to the computing devices that...

SAP Software

SAP is an end-to-end enterprise solution provider specializing in enterprise resource...

Chief Operating Officer (COO)

The chief operating officer (COO) is a member of a company's senior executive...

Kanban

Kanban is a workflow management method intended to define, manage, and improve services...