Serverless refers to a cloud computing approach where developers can build and run applications without having to manage the underlying infrastructure, such as servers or server instances. In the serverless model, the responsibility for provisioning, scaling, and maintaining servers lies with a cloud service provider.

Essentially, serverless doesn’t mean there are no servers; it means developers don't need to concern themselves with managing those servers. The infrastructure is automatically managed and scaled by the provider as needed, allowing developers to focus on writing application code without worrying about the underlying hardware or server configuration.

Serverless applications are often broken down into functions or services known as "Function-as-a-Service" (FaaS). Developers write functions that respond to specific events and are managed and executed by the serverless provider. These functions scale on demand and are billed based on actual usage.

Benefits of serverless include improved scalability, cost savings through usage-based billing, reduced operational complexity, and the ability to focus on developing application logic rather than managing infrastructure. It's commonly used for various types of applications such as web applications, APIs, data processing, and more.

Cloud computing refers to the delivery of computing resources over the internet. Instead of using local servers or personal devices to store data or run applications, cloud services are provided and managed by a provider over the internet.

There are different types of cloud services:

1. Infrastructure as a Service (IaaS): It provides basic computing resources such as virtual machines, storage, and networking. Users can utilize and manage these resources without owning physical hardware.

2. Platform as a Service (PaaS): It offers a platform for developers to build, run, and manage applications without worrying about the underlying infrastructure. This includes databases, development tools, and middleware.

3. Software as a Service (SaaS): Fully hosted applications that can be accessed and used over the internet without requiring installations or updates on the users' devices. Examples include email services, office suites, and CRM systems.

Cloud computing offers numerous benefits, including scalability, flexibility, cost-effectiveness (through usage-based billing), easier access to resources, and regular updates to services provided by the vendor.

It's used across various domains, from businesses looking to outsource their infrastructure to developers aiming to build scalable applications. The cloud has significantly transformed how resources are provisioned and applications are developed.