# Null-Coalescing Operator

The ?? operator, which uses a fallback when its left value is null.

## What does **Null-Coalescing Operator** do in C#?

**Null-Coalescing Operator** — The ?? operator, which uses a fallback when its left value is null.

```csharp
class Profile
{
    string DisplayName(string? nickname)
    {
        return nickname ?? "Guest";
    }
}
```

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Updated: September 27, 2026

Source: https://www.ask-codey.com/glossary/null-coalescing-operator