DLL

Stands for "Dynamic Link Library."

A DLL is a compiled library of functions, data, and other resources that programs running in Windows may use. Any program can access the code in a DLL, and multiple programs may access a DLL at the same time. Accessing a shared code library means that programs don't need to include that code in their executable files, which helps them to use less storage space and system memory.

When a program needs to access the functions and resources in a DLL file, it loads it into system memory at runtime and creates links to the resources it needs. This process is called dynamic linking, and it allows the program to use the functions, data, and resources in the DLL as if they were included in the program itself. However, a program that depends on dynamic linking won't run if any of its DLL files are missing.

Windows includes thousands of DLL files containing system functions and resources
Windows includes thousands of DLL files containing system functions and resources

Windows includes many DLL files that contain basic system resources like API functions, device drivers, and user interface elements. Any program running on Windows may access these DLL files to use those shared resources. Third-party programs may install additional DLL files, offloading functions and data to allow the program to run more efficiently. DLL files may also receive updates separately from the programs that call them to fix bugs without recompiling the entire application.

NOTE: The opposite of dynamic linking is static linking, which links a program's libraries and dependencies to the executable file during compilation. The resulting executable file is larger but runs without any additional files.

File Extensions: .DLL

Updated May 4, 2023 by Brian P.

quizTest Your Knowledge

NoSQL is a type of what?

A
Operating system
0%
B
Markup language
0%
C
Malware
0%
D
Database
0%
Correct! Incorrect!     View the NoSQL definition.
More Quizzes →

The Tech Terms Computer Dictionary

The definition of DLL on this page is an original definition written by the TechTerms.com team. If you would like to reference this page or cite this definition, please use the green citation links above.

The goal of TechTerms.com is to explain computer terminology in a way that is easy to understand. We strive for simplicity and accuracy with every definition we publish. If you have feedback about this definition or would like to suggest a new technical term, please contact us.

Sign up for the free TechTerms Newsletter

How often would you like to receive an email?

You can unsubscribe or change your frequency setting at any time using the links available in each email.

Questions? Please contact us.