What is the usage of the “fixed” keyword in C#?

In C#, the fixed keyword is used to create an array of a fixed size that cannot be moved in memory. This keyword is typically used in conjunction with pointers to access unmanaged memory in C#. When an array is defined using the fixed keyword, its elements remain stationary in memory, which can improve performance and prevent interference from the garbage collector. The fixed keyword is commonly used when interacting with external unmanaged code or when directly manipulating memory is required.