What is the difference between the ref and out keywords in C#?

Hello everyone! I started learning C# and came across the `ref` and `out` keywords. I understand that they both allow modifying passed variables inside a method, but the difference between them is not entirely clear to me. Here's an example I wrote: ```csharp public void TestRef(ref int x) { x = x * 2; } public void TestOut(out int x) { x = 10; } static void Main() { int a = 5; int b; // Error: uninitialized variable for out TestRef(ref a); Console.WriteLine(a); // Outputs 10 TestOut(out b); Console.WriteLine(b); // Outputs 10 } ``` I noticed that with `out` I cannot pass an uninitialized variable without an error, but I initialize it inside the method. And with `ref`, I must initialize the variable before the call. But this is not the only difference.