# Go Interfaces (Go)

> Interfaces, type assertions, type switches, empty interface, error interface

- 18 interview questions
- Junior
- [Interview Questions: Go](https://sharpskill.dev/en/technologies/go/interview-questions.md)

## 1. What is an interface in Go?

**Answer**

An interface in Go is a type that defines a set of method signatures. A type implements an interface implicitly by defining all its methods, without explicit declaration. This enables strong decoupling and flexibility in Go program design.

## 2. How does a type implement an interface in Go?

**Answer**

In Go, interface implementation is implicit: a type just needs to define all the methods of the interface. No explicit declaration (like 'implements' in Java) is needed. This allows adding interfaces to existing types without modifying their source code.

## 3. What is special about the empty interface (interface{}) in Go?

**Answer**

The empty interface (interface{}) defines no methods, which means all types automatically implement it. It can therefore hold a value of any type. Since Go 1.18, it is aliased by the predeclared type 'any' for better clarity.

## 15 more questions available

- Since Go 1.18, what is the alias for the interface{} type?
- What is the syntax for a type assertion in Go?

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## Other Go interview topics

- [Go Basics](https://sharpskill.dev/en/technologies/go/interview-questions/go-basics.md): 25 questions, Junior
- [Go Data Structures](https://sharpskill.dev/en/technologies/go/interview-questions/go-data-structures.md): 20 questions, Junior
- [Error Handling](https://sharpskill.dev/en/technologies/go/interview-questions/error-handling.md): 20 questions, Junior
- [Goroutines Basics](https://sharpskill.dev/en/technologies/go/interview-questions/goroutines-basics.md): 20 questions, Junior
- [Channels](https://sharpskill.dev/en/technologies/go/interview-questions/channels.md): 22 questions, Junior
- [Go Modules](https://sharpskill.dev/en/technologies/go/interview-questions/go-modules.md): 18 questions, Mid-Level
- [HTTP Server](https://sharpskill.dev/en/technologies/go/interview-questions/http-server.md): 24 questions, Mid-Level
- [HTTP Client](https://sharpskill.dev/en/technologies/go/interview-questions/http-client.md): 18 questions, Mid-Level
- [JSON Encoding](https://sharpskill.dev/en/technologies/go/interview-questions/json-encoding.md): 20 questions, Mid-Level
- [Database/SQL](https://sharpskill.dev/en/technologies/go/interview-questions/database-sql.md): 22 questions, Mid-Level
- [Context Package](https://sharpskill.dev/en/technologies/go/interview-questions/context-package.md): 20 questions, Mid-Level
- [Testing](https://sharpskill.dev/en/technologies/go/interview-questions/testing.md): 22 questions, Mid-Level
- [Concurrency Patterns](https://sharpskill.dev/en/technologies/go/interview-questions/concurrency-patterns.md): 24 questions, Mid-Level
- [Sync Primitives](https://sharpskill.dev/en/technologies/go/interview-questions/sync-primitives.md): 22 questions, Mid-Level
- [Go Web Frameworks](https://sharpskill.dev/en/technologies/go/interview-questions/go-web-frameworks.md): 20 questions, Mid-Level
- [REST API Design](https://sharpskill.dev/en/technologies/go/interview-questions/rest-api-design.md): 20 questions, Mid-Level
- [gRPC](https://sharpskill.dev/en/technologies/go/interview-questions/grpc.md): 22 questions, Mid-Level
- [Reflection](https://sharpskill.dev/en/technologies/go/interview-questions/reflection.md): 20 questions, Senior
- [Memory Management](https://sharpskill.dev/en/technologies/go/interview-questions/memory-management.md): 24 questions, Senior
- [Performance Optimization](https://sharpskill.dev/en/technologies/go/interview-questions/performance-optimization.md): 22 questions, Senior
- [Generics](https://sharpskill.dev/en/technologies/go/interview-questions/generics.md): 20 questions, Senior
- [Go Design Patterns](https://sharpskill.dev/en/technologies/go/interview-questions/design-patterns.md): 24 questions, Senior
- [Microservices](https://sharpskill.dev/en/technologies/go/interview-questions/microservices.md): 24 questions, Senior
- [Security & Authentication](https://sharpskill.dev/en/technologies/go/interview-questions/security-authentication.md): 24 questions, Senior
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- [Kubernetes Basics](https://sharpskill.dev/en/technologies/go/interview-questions/kubernetes-basics.md): 22 questions, Senior
- [Advanced Go](https://sharpskill.dev/en/technologies/go/interview-questions/advanced-go.md): 20 questions, Senior
- [CLI Development](https://sharpskill.dev/en/technologies/go/interview-questions/cli-development.md): 20 questions, Senior

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