Update docs 1 (#71812)

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docs/02-app/02-api-reference/01-directives/index.mdx

@@ -0,0 +1,6 @@
+---
+title: Directives
+description: Directives are used to modify the behavior of your Next.js application.
+---
+
+The following directives are available:

docs/02-app/02-api-reference/01-directives/use-client.mdx

@@ -0,0 +1,95 @@
+---
+title: use client
+description: Learn how to use the use client directive to render a component on the client.
+related:
+  description: React documentation for use client.
+  links: 
+    - https://react.dev/reference/rsc/use-client
+---
+
+The `use client` directive designates a component to be rendered on the **client side** and should be used when creating interactive user interfaces (UI) that require client-side JavaScript capabilities, such as state management, event handling, and access to browser APIs. This is a React feature.
+
+## Usage
+
+To designate a component as a Client Component, add the `use client` directive **at the top of the file**, before any imports:
+
+````tsx filename="app/components/counter.tsx" highlight={1} switcher
+'use client'
+
+import { useState } from 'react'
+
+export default function Counter() {
+  const [count, setCount] = useState(0)
+
+  return (
+    <div>
+      <p>Count: {count}</p>
+      <button onClick={() => setCount(count + 1)}>Increment</button>
+    </div>
+  )
+}
+````
+
+````jsx filename="app/components/counter.js" highlight={1} switcher
+'use client'
+
+import { useState } from 'react'
+
+export default function Counter() {
+  const [count, setCount] = useState(0)
+
+  return (
+    <div>
+      <p>Count: {count}</p>
+      <button onClick={() => setCount(count + 1)}>Increment</button>
+    </div>
+  )
+}
+````
+
+## Nesting Client Components within Server Components
+
+Combining Server and Client Components allows you to build applications that are both performant and interactive:
+
+1. **Server Components**: Use for static content, data fetching, and SEO-friendly elements.
+2. **Client Components**: Use for interactive elements that require state, effects, or browser APIs.
+3. **Component composition**: Nest Client Components within Server Components as needed for a clear separation of server and client logic.
+
+In the following example:
+
+- `Header` is a Server Component handling static content.
+- `Counter` is a Client Component enabling interactivity within the page.
+
+```tsx filename="app/page.tsx" highlight={2,8} switcher
+import Header from './header'
+import Counter from './counter' // This is a Client Component
+
+export default function Page() {
+  return (
+    <div>
+      <Header />
+      <Counter />
+    </div>
+  )
+}
+```
+
+```jsx filename="app/page.js" highlight={2,8} switcher
+import Header from './header'
+import Counter from './counter' // This is a Client Component
+
+export default function Page() {
+  return (
+    <div>
+      <Header />
+      <Counter />
+    </div>
+  )
+}
+```
+
+
+## Reference
+
+See the [React documentation](https://react.dev/reference/rsc/use-client) for more information on `use client`.
+

docs/02-app/02-api-reference/01-directives/use-server.mdx

@@ -0,0 +1,158 @@
+---
+title: use server
+description: Learn how to use the use server directive to execute code on the server.
+related:
+  description: React documentation for use server.
+  links: 
+    - https://react.dev/reference/rsc/use-server
+---
+
+The `use server` directive designates a function or file to be executed on the **server side**. It can be used at the top of a file to indicate that all functions in the file are server-side, or inline at the top of a function to mark the function as a [Server Function](https://19.react.dev/reference/rsc/server-functions). This is a React feature.
+
+## Using `use server` at the top of a file
+
+The following example shows a file with a `use server` directive at the top. All functions in the file are executed on the server.
+
+```tsx filename="app/actions.ts" highlight={1} switcher
+'use server'
+import { db } from '@/lib/db' // Your database client
+
+export async function createUser(data: { name: string; email: string }) {
+  const user = await db.user.create({ data })
+  return user
+}
+```
+
+```jsx filename="app/actions.js" highlight={1} switcher
+'use server'
+import { db } from '@/lib/db' // Your database client
+
+export async function createUser(data) {
+  const user = await db.user.create({ data })
+  return user
+}
+```
+
+### Using Server Functions in a Client Component
+
+To use Server Functions in Client Components you need to create your Server Functions in a dedicated file using the `use server` directive at the top of the file. These Server Functions can then be imported into Client and Server Components and executed.
+
+Assuming you have a `fetchUsers` Server Function in `actions.ts`:
+
+```tsx filename="app/actions.ts" highlight={1} switcher
+'use server'
+import { db } from '@/lib/db' // Your database client
+
+export async function fetchUsers() {
+  const users = await db.user.findMany()
+  return users
+}
+```
+
+```jsx filename="app/actions.js" highlight={1} switcher
+'use server'
+import { db } from '@/lib/db' // Your database client
+
+export async function fetchUsers() {
+  const users = await db.user.findMany()
+  return users
+}
+```
+
+Then you can import the `fetchUsers` Server Function into a Client Component and execute it on the client-side.
+
+```tsx filename="app/components/my-button.tsx" highlight={1,2,8} switcher
+'use client'
+import { fetchUsers } from '../actions'
+
+export default function MyButton() {
+  return <button onClick={() => fetchUsers()}>Fetch Users</button>
+}
+```
+
+```jsx filename="app/components/my-button.js" highlight={1,2,8} switcher
+'use client'
+import { fetchUsers } from '../actions'
+
+export default function MyButton() {
+  return <button onClick={() => fetchUsers()}>Fetch Users</button>
+}
+```
+
+
+## Using `use server` inline
+
+In the following example, `use server` is used inline at the top of a function to mark it as a [Server Function](https://19.react.dev/reference/rsc/server-functions):
+
+```tsx filename="app/page.tsx" highlight={5} switcher
+import { db } from '@/lib/db' // Your database client
+ 
+export default function UserList() {
+  async function fetchUsers() {
+    'use server'
+    const users = await db.user.findMany()
+    return users
+  }
+
+  return <button onClick={() => fetchUsers()}>Fetch Users</button>
+}
+```
+
+```jsx filename="app/page.js" highlight={5} switcher
+import { db } from '@/lib/db' // Your database client
+
+export default function UserList() {
+  async function fetchUsers() {
+    'use server'
+    const users = await db.user.findMany()
+    return users
+  }
+
+  return <button onClick={() => fetchUsers()}>Fetch Users</button>
+}
+```
+
+## Security considerations
+
+When using the `use server` directive, it's important to ensure that all server-side logic is secure and that sensitive data remains protected.
+
+### Authentication and authorization
+
+Always authenticate and authorize users before performing sensitive server-side operations.
+
+```tsx filename="app/actions.ts" highlight={1,7,8,9,10} switcher
+'use server'
+
+import { db } from '@/lib/db' // Your database client
+import { authenticate } from '@/lib/auth' // Your authentication library
+
+export async function createUser(data: { name: string; email: string }, token: string) {
+  const user = authenticate(token)
+  if (!user) {
+    throw new Error('Unauthorized')
+  }
+  const newUser = await db.user.create({ data })
+  return newUser
+}
+```
+
+```jsx filename="app/actions.js" highlight={1,7,8,9,10} switcher
+'use server'
+
+import { db } from '@/lib/db' // Your database client
+import { authenticate } from '@/lib/auth' // Your authentication library
+
+export async function createUser(data, token) {
+  const user = authenticate(token)
+  if (!user) {
+    throw new Error('Unauthorized')
+  }
+  const newUser = await db.user.create({ data })
+  return newUser
+}
+```
+
+
+## Reference
+
+See the [React documentation](https://react.dev/reference/rsc/use-server) for more information on `use server`.

docs/02-app/02-api-reference/02-file-conventions/route-segment-config.mdx → docs/02-app/02-api-reference/03-file-conventions/route-segment-config.mdx

@@ -3,6 +3,8 @@ title: Route Segment Config
 description: Learn about how to configure options for Next.js route segments.
 ---
 
+> The options outlined on this page are disabled if the [`dynamicIO`](/docs/app/api-reference/next-config-js/dynamicIO) flag is on, and will eventually be deprecated in the future.
+
 The Route Segment options allows you to configure the behavior of a [Page](/docs/app/building-your-application/routing/layouts-and-templates), [Layout](/docs/app/building-your-application/routing/layouts-and-templates), or [Route Handler](/docs/app/building-your-application/routing/route-handlers) by directly exporting the following variables:
 
 | Option                                  | Type                                                                                                                      | Default                    |