1.1 The History1.2 Characters Used in C1.3 Data Types1.3.1 Integer Data Type (int)1.3.2 Character Data Type (char)1.3.3 The Floating Point (f loat) Data Type1.4 C Tokens1.4.1 Identifiers1.4.2 Keywords1.4.3 Variables1.4.4 Constants1.5 Structure of a C Program1.5.1 Our First Program1.6 printf () and scanf () Functions1.6.1 How to Display Data Using printf() Function1.6.2 How to Read Data from Keyboard Using scanf()1.7 Comments1.8 Escape Sequence (Backslash Character Constants)1.9 Operators and Expressions1.9.1 Arithmetic Operators1.9.2 Relational and Logical Operators1.9.3 Conditional Operator1.9.4 Order of Evaluation of Expressions1.9.5 Some Special Operators1.9.6 Assignment Operator1.9.7 Bitwise Shift Operators1.10 Flow of Control1.10.1 The Compound Statement1.10.2 Selective Execution (Conditional Statements)1.10.3 Repetitive Execution (Iterative Statements)1.10.4 The exit() Function1.10.5 Nested Loops1.10.6 The Goto Statement (Unconditional Branching)1.11 Input–Output Functions (I/O)1.11.1 Buffered I/O1.11.2 Single Character Functions1.11.3 String-based Functions1.12 Arrays1.13 Structures1.13.1 Defining a Structure in C1.13.2 Referencing Structure Elements1.13.3 Arrays of Structures1.13.4 Initializing Structures1.13.5 Assignment of Complete Structures1.13.6 Nested Structures1.14 User-defined Data Types1.14.1 Enumerated Data Types1.15 Unions1.16 Functions1.16.1 Function Prototypes1.16.2 Calling a Function1.16.3 Parameter Passing in Functions1.16.4 Returning Values from Functions1.16.5 Passing Structures to Functions1.17 Recursion1.17.1 Types of Recursion1.17.2 Tower of Hanoi