What are records in C#?

Question

Accepted Answer

**Records** — immutable reference types with built-in value equality.

**Definition:**
```csharp
// Positional record
public record Person(string Name, int Age);

// Traditional record
public record Address
{
    public string Street { get; init; }
    public string City { get; init; }
}
```

**Built-in features:**
- Value-based equality (Equals, GetHashCode).
- ToString() with all properties.
- Deconstruction.
- Init-only properties.

**Record struct (C# 10):**
```csharp
public readonly record struct Point(int X, int Y);
```

**Use cases:**
- DTOs and data models.
- Value objects in DDD.
- Immutable state.
- Pattern matching.

**vs class:**
- Records: value equality, immutability.
- Classes: identity, mutable state.

C#: What are records in C#?