The basics of Go errors - the error interface, returning and checking errors with if err != nil, and creating errors with errors.New and fmt.Errorf.

• The Error Interface
• Returning And Checking Errors
• Creating Errors With errors.New And fmt.Errorf

Add context to errors with %w, check them with errors.Is and errors.As, and return several at once with errors.Join.

• Wrapping Errors With %w
• errors.Is And errors.As
• Combining Errors With errors.Join

Choose between sentinel errors and custom error types, decide when to panic instead of returning an error, and avoid the nil error interface trap.

• Sentinel Errors Vs Custom Error Types
• Panic Vs Returning An Error
• The Nil Error Interface Trap

The most common Go error handling mistakes with their exact messages, plus practical patterns for HTTP handlers and file reading.

• Common Error Handling Mistakes
• Errors In HTTP Handlers
• Errors When Reading Files