In Golang, error handling is an important aspect of writing reliable and robust code. The language provides a simple and explicit mechanism for handling errors. Here’s how error handling works in Go and some common error handling patterns:

1. Error Type: In Go, errors are represented by the `error` interface, which is a built-in interface defined as follows:

type error interface {
  Error() string
}

Any type that implements the `Error()` method with the signature `Error() string` satisfies the `error` interface.

2. Error Handling: When a function in Go encounters an error, it typically returns it as the last return value. The caller is responsible for checking the returned error and handling it appropriately. A common pattern is to use an `if` statement to check if the error is `nil` (indicating no error) and handle the error if it is not `nil`.

  result, err := SomeFunction()
  if err != nil {
      // Handle the error
  } else {
      // Proceed with successful result
  }

It is important to handle errors explicitly rather than ignoring them to ensure proper error propagation and prevent unexpected behavior.

3. Error Propagation: When a function encounters an error but cannot handle it, it can return the error to its caller, propagating it up the call stack. This allows errors to be handled at higher levels where more context-specific error handling can take place.

4. Custom Errors: Go allows you to define custom error types by creating new types that implement the `error` interface. Custom errors can provide additional information or context about the error.

  type MyError struct {
      Message string
  }
 
  func (e MyError) Error() string {
      return e.Message
  }

   Custom errors can be used to differentiate between different types of errors or provide more descriptive error messages.

5. Multiple Return Values: Go’s support for multiple return values is particularly useful for error handling. Functions often return both a result and an error value, allowing the caller to easily check for errors and handle them appropriately.

6. Panic and Recover: In exceptional cases where a program encounters an unrecoverable error or an exceptional condition, Go provides the `panic` function to trigger a runtime panic. Panics are typically used for exceptional situations and should not be used for normal error handling. The `recover` function can be used to catch and handle panics, allowing for graceful program termination or error reporting.

  defer func() {
      if r := recover(); r != nil {
          // Handle the panic
      }
  }()

It’s important to note that panics() and recover() should be used judiciously and only in exceptional circumstances.

These are some common error-handling patterns in Go. By explicitly returning error values, propagating errors up the call stack, and using custom error types when needed, Go ensures a straightforward and reliable approach to error handling.