Static Library vs Dynamic Linked Library (Lib vs. DLL)

The Kool Aid: “Using dynamic linking instead of static linking offers several advantages. DLLs save memory, reduce swapping, save disk space, upgrade easier, provide after-market support, provide a mechanism to extend the MFC library classes, support multilanguage programs, and ease the creation of international versions.”

Lib -This is a code “bundle” inside your .exe	DLL -This is a stand alone unit of code.
Performance
Code is always loaded with the executable Can speed up app load time	Small hit when the .dll loads  Can be deferred at App load time
Compiled Size
Larger file size for .exe	Many smaller files
ALM
Can only be used at compile time. Not prone to versioning problems. You will need to take extra steps to get the PDB’s rolled into the DLL PDB Must update each product which uses it separately Fights incompatibility issues requires you to replace the exe for upgrades. Some say Lib’s make it easier to support many platforms	Modularity Can Be used by multiple Applications. Can speed up development (reduced compile time) Can cause versioning problems. Can upgrade all products at once if dll is shared across product lines Forces you to update all related projects and can cause compatibility maintenance issues across your organization. Allows you to upgrade the application by replacing just the dll. Can make it easier to support new hardware or hardware changes
Operation
Used by the compiler at compile-time. Results in 1 Large file. Avoids dependency issues	Compiled and called at runtime. Results in many smaller files. Can be stored in the GAC
Misc.
All iOS binaries are static libs	Original implantation was the origin of DLL Hell Your Exe will produce a minimal Lib file at compile time to link to the dll Allow a game to easily support mods.
Architectural Consideration
Special care need to be taken when internal dependencies are not straight forward.	Allows for inter-process communication
Legal Implications
If you use an LGPL library statically your code automatically becomes Open Sourced	If you use an LGPL library then you only have to open source the changes made to that library/
Security
Everything is internal to the exe, thus contained	Data can potentially be ‘hacked’

If you are developing for windows 8 (win8)  then the quick answer is use a DLL

If your Developing for iOS then use a Lib

 

References:

• http://stackoverflow.com/questions/140061/when-to-use-dynamic-vs-static-libraries
• http://social.msdn.microsoft.com/Forums/en-US/vcgeneral/thread/830bf2ad-3b42-43e2-963c-c0566b991f89/
• http://www.differencebetween.net/technology/difference-between-lib-and-dll/
• http://en.wikipedia.org/wiki/Dynamic-link_library
• http://en.wikipedia.org/wiki/Static_library
• http://cboard.cprogramming.com/cplusplus-programming/30841-lib-vs-h-vs-dll.html
• http://msdn.microsoft.com/en-us/library/1ez7dh12(v=vs.110).aspx