Lock is a device used to fasten or secure something, typically operated by a key or combination.
In computing, lock refers to a synchronization mechanism for enforcing limits on access to a resource in an environment where there are many threads of execution.
The term "lock" also refers to:
1. A section of a canal or river confined within gates for raising or lowering boats
2. A wrestling hold that prevents an opponent from moving
3. A mechanism for firing a gun
4. A curl or bunch of hair