1. Introduction to Pointers

1.1 What are Pointers? 
 A pointer is a variable that stores the memory address of another variable. Instead of holding a data value directly, a pointer "points to" the location in memory where the data is stored. 
 Analogy: 
Think of computer memory like a street with houses: 
 
 Each house (memory location) has an address (memory address) 
 Each house contains something (data value) 
 A pointer is like writing down a house address on paper 
 You can use that address to find and access the house 
 
 Why Use Pointers? 
 
 Dynamic Memory Allocation: Create variables at runtime 
 Efficient Array/String Manipulation: Access elements without copying 
 Function Parameter Passing: Modify variables from within functions 
 Data Structures: Build linked lists, trees, graphs, etc. 
 System Programming: Direct memory access and hardware interaction 
 
 1.2 Memory Addresses 
 Every variable in C is stored at a specific memory location, identified by a unique address. 
 #include <stdio.h>

int main() {
 int age = 25;
 float height = 5.9f;
 char grade = 'A';
 
 printf("Value of age: %d\n", age);
 printf("Address of age: %p\n", (void*)&age);
 
 printf("Value of height: %.1f\n", height);
 printf("Address of height: %p\n", (void*)&height);
 
 printf("Value of grade: %c\n", grade);
 printf("Address of grade: %p\n", (void*)&grade);
 
 return 0;
}

/* Output (addresses will vary):
Value of age: 25
Address of age: 0x7ffd5c8e4a3c
Value of height: 5.9
Address of height: 0x7ffd5c8e4a38
Value of grade: A
Address of grade: 0x7ffd5c8e4a37
*/
 
 Key Points: 
 
 Memory addresses are typically displayed in hexadecimal (base 16) 
 The & operator gets the address of a variable 
 Format specifier %p prints pointer/address values 
 Adjacent variables may have addresses close to each other