C Questions#1

Important C Questions

What does static variable mean?
What is a pointer?
What is a structure?
What are the differences between structures and arrays?
In header files whether functions are declared or defined?
What are the differences between malloc() and calloc()?
What are macros? what are its advantages and disadvantages?
Difference between pass by reference and pass by value?
What is static identifier?
Where are the auto variables stored?
Where does global, static, local, register variables, free memory and C Program instructions get stored?
Difference between arrays and linked list?
What are enumerations?