Why are static libraries needed in linux?

Question

linux

gcc allows you to create static libraries and then link them at compile time.
The question is, why are static libraries needed and in what cases should they be used?

Answer 1

When a program is linked with dynamic libraries, the executable file will not run if the dynamic libraries it needs are not installed on the system or are not nearby. And a statically linked program is one executable file that will definitely work everywhere (if the ABI is suitable in the system, of course).
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