Final answer:
In programming, specifically C or C++, variables inside blocks have automatic linkage, meaning they are created when the block is entered and destroyed when it is exited. They also have no linkage outside the block where they're declared.
Step-by-step explanation:
When discussing variables within a programming context, particularly in the C or C++ languages, variables defined inside of blocks have automatic linkage by default. This means these variables are automatically allocated when the block in which they are defined is entered, and they are deallocated when the block is exited. Scope and linkage control the visibility and lifespan of a variable. Local variables inside blocks, such as those declared within a function or a loop, are not visible outside that block and they have no linkage, which means they are not known outside the block where they are declared.
Example of Automatic Linkage
An example of automatic linkage is a variable declared within a function: whenever the function is called, the variable is created, and it is destroyed when the function returns. This is in contrast to variables with external or static linkage which maintain their existence throughout the program run.