Service Locator
In plain terms
A registry that provides dependencies on request.
Going deeper
The Service Locator pattern centralizes a registry that components query to obtain their dependencies at runtime. Components pull what they need from it.
Under the hood
An alternative to dependency injection, often criticized for hiding dependencies and hurting testability.
Examples
Dependency lookup, plugin registries, legacy DI, runtime resolution.
Think of it like...
Like a help desk you ask whenever you need a service, rather than being handed it upfront.