'int' is used for integers and stores whole numbers, while 'float' is used for floating-point numbers and stores real numbers with decimal points. 'int' offers better precision, while 'float' offers a larger range and can represent fractions.

A pointer is a variable that holds the memory address of another variable. Pointers allow direct memory access and enable dynamic memory allocation. They are used to implement data structures, pass by reference, and interact with hardware.

'malloc' is used to dynamically allocate memory during runtime. It returns a pointer to the allocated memory. 'free' is used to release memory allocated using 'malloc.' Failure to release memory can lead to memory leaks.

A structure is a composite data type that groups variables of different types under a single name. A union stores variables of different data types in the same memory location, allowing memory optimization. Structures have separate memory for each member, while unions share memory.

The 'const' keyword is used to define constants in C. It indicates that a variable's value cannot be changed once it's assigned. This is useful for defining read-only variables and for preventing accidental modification of data.

C provides 'for,' 'while,' and 'do-while' loops. 'for' loops are used when you know the number of iterations beforehand. 'while' loops are used when you want to loop based on a condition. 'do-while' loops are similar to 'while' loops but guarantee that the loop body is executed at least once.

'break' is used to exit a loop prematurely, terminating the loop and moving to the next statement after it. 'continue' is used to skip the current iteration of a loop and jump to the next iteration without exiting the loop.

Recursion is a programming technique where a function calls itself. It's often used for solving problems that can be divided into smaller, similar subproblems. For example, the factorial of a number can be calculated using recursion: int factorial(int n) { if (n == 0) return 1; return n * factorial(n - 1); }

The 'switch' statement is used for multi-way branching. It allows you to choose one of several code blocks to execute based on the value of an expression. It's a more efficient alternative to multiple 'if-else' statements when you have many possible conditions to check.

An array is a collection of elements of the same data type stored in contiguous memory locations. A pointer, on the other hand, is a variable that stores the memory address of another variable. While an array has a fixed size, a pointer can be reassigned to point to different memory locations.

'strcpy' is used to copy a string from one location to another until a null terminator ('') is encountered. 'strncpy' copies a specified number of characters from one string to another, ensuring that the destination is null-terminated, but it may not copy the entire source string.

The 'volatile' keyword is used to indicate to the compiler that a variable's value may change at any time, without any action being taken by the code. This prevents the compiler from optimizing away reads or writes to the variable, which is essential for variables that are accessed by hardware or external factors.

'static' is used to declare variables with internal linkage, meaning they are limited to the file where they are defined. 'extern' is used to declare variables that are defined in another file and have external linkage, making them accessible across multiple files in a program.

Bitwise operators in C perform operations on individual bits of integers. The main bitwise operators are '&' (bitwise AND), '|' (bitwise OR), '^' (bitwise XOR), '~' (bitwise NOT), '<<' (left shift), and '>>' (right shift). They are used for tasks such as setting or clearing specific bits, checking bit flags, and optimizing code for bit-level operations.