Syntax, Variables, Data Types, Operators, and Input Output

Variables and Data Types

int age = 25;
double salary = 52000.75;
char grade = 'A';
bool isActive = true;
string name = "Alice";

C# is strongly typed and expressive. It gives developers a rich set of built-in types and clear syntax for declaring and initializing values.

Type Categories

decimal is especially useful in money-related applications because it avoids some binary floating-point accuracy issues.

Console Input and Output

Console.Write("Enter your name: ");
string? userName = Console.ReadLine();
Console.WriteLine($"Hello, {userName}");

String interpolation with $"" is one of the most readable features in C#. Students should learn it early because it improves clarity.

Operators and Expressions

int a = 10;
int b = 3;
int sum = a + b;
bool result = a > b && b > 0;
int remainder = a % b;

C# supports arithmetic, relational, logical, assignment, null-coalescing, conditional, and many other operators. Students should understand precedence and keep expressions readable.

Type Inference with var

var city = "Berlin";
var count = 5;

var does not make C# dynamically typed. The compiler still determines the type statically. Good style means using var when it improves readability, not when it hides meaning.

Real-World Usage Snapshot

These basics appear everywhere from console apps to enterprise APIs. Correct type choices, readable expressions, and good output formatting help prevent confusion later in business logic and data processing code.