Summary  
This chapter explains how to define dynamic URL segments as route parameters and extract their values in route handlers to work with specific resources by identifier.

General domain of usage  
User management APIs



Route parameters allow you to pass dynamic values in the URL.

For example, instead of requesting all users, you can request a specific user by ID.

Define a route parameter like this:

```ts 
import { Controller, Get, Param } from '@nestjs/common';

@Controller('users')
export class UsersController {
  @Get(':id')
  getUserById(@Param('id') id: string) {
    return `User ID: ${id}`;
  }
}
```

<br>

* `:id`: defines a dynamic part of the URL;
* `@Param('id')`: extracts the value from the URL;
* `id`: is passed into the method.

When you open:

```bash 
/users/5
```

The response will be:

```bash 
User ID: 5
```

You can use route parameters whenever you need to work with specific data, such as users, products, or orders.


What decorator is used to access route parameters in Nest.js?

Learn how to build structured backend applications with Nest.js. Organize your code using controllers, services, and modules, handle requests and data validation, and create a complete API using a scalable architecture.

Working with Route Parameters