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# Overview

The SignalWire platform models every callable thing — a person, a room,
an AI agent, a SWML script — as a [**Resource**](/docs/platform/resources).
Each Resource is reachable via one or more [**Addresses**](/docs/platform/addresses)
in the form `/<context>/<name>` (e.g. `/private/jane`, `/public/support`).
**Users** (called [**Subscribers**](/docs/platform/subscribers) on the platform) are the Resource type that represents a person in your
application, with credentials, identity, and assigned phone numbers.

The Browser SDK exposes three handles for working with these platform
concepts at runtime, all hanging off the connected `SignalWire`
client:

| Platform concept                                                  | SDK access point                         | What it gives you                                                               |
| ----------------------------------------------------------------- | ---------------------------------------- | ------------------------------------------------------------------------------- |
| The authenticated [User](/docs/platform/subscribers) (Subscriber) | `client.user` / `client.user$`           | Identity (id, email, name, company), assigned addresses, SAT claims.            |
| The [Addresses](/docs/platform/addresses) reachable to that user  | `client.directory` / `client.directory$` | Paginated, observable list of [`Address`] entries — search, dial, message.      |
| Per-client settings                                               | `client.preferences`                     | Device choices, media defaults, ICE/recovery tuning — optionally persisted.     |
| Per-call capability flags                                         | `call.self.capabilities`                 | What the current participant is allowed to do (mute, layout, screenshare, end). |

This section walks through each one in turn.

## Naming note: [`User`] vs "Subscriber"

The Browser SDK calls this resource a **User** (`client.user`). The
platform still uses the name **Subscriber** in several places:

* The credential is still called a **Subscriber Access Token** (SAT).
* The REST API endpoints are still `/api/fabric/subscribers/...`.
* The Dashboard still shows a **Subscribers** tab.
* The [`Address`] for one of these resources still has `type === 'subscriber'`.

**User and Subscriber refer to the same thing.** When you read
"Subscriber" in platform docs or dashboard UI, the SDK-side
equivalent is `client.user`.

## How they fit together

```
                           ┌──────────────────────────────┐
                           │   SignalWire (platform)      │
                           │   Resources + Addresses      │
                           └──────────────┬───────────────┘
                                          │  REST mint
                                          ▼
                           ┌──────────────────────────────┐
       Backend mints SAT  │   Subscriber Access Token    │
       on user login   ─► │   for THIS user               │
                           └──────────────┬───────────────┘
                                          │  passed to SDK
                                          ▼
        ┌────────────────────────────────────────────────────────────┐
        │   const client = new SignalWire(provider)                  │
        │                                                            │
        │   client.user$         ─►  this user's profile              │
        │   client.directory$    ─►  addresses they can reach        │
        │   client.preferences   ─►  their per-client settings        │
        │                                                            │
        │   const call = await client.dial(address)                  │
        │   call.self.capabilities  ─►  what they may do in THIS call │
        └────────────────────────────────────────────────────────────┘
```

The platform decides which Addresses a user can reach (based on
context, ACLs, and the SAT's scopes). The SDK surfaces that as an
observable directory — your UI doesn't have to know how the platform
arrives at the list.

## What you'll find in this section

#### [Users](/docs/browser-sdk/v4/guides/users)

Working with `client.user`: profile fields, assigned addresses,
push notification keys, and the User / Subscriber naming.

#### [Address Book & Directory](/docs/browser-sdk/v4/guides/address-book)

`client.directory` and the [`Address`] entity: paginated listing,
lookup by URI, channels, messaging, and call history.

#### [Client Preferences](/docs/browser-sdk/v4/guides/client-preferences)

`client.preferences`: persisted device choices, media defaults,
custom `userVariables`, and ICE / recovery tuning.

#### [Capabilities](/docs/browser-sdk/v4/guides/capabilities)

`call.self.capabilities`: drive your UI off real server-granted
permissions instead of guessing what a participant may do.

For creating Users (Subscribers), minting tokens, or managing Resources from
your backend, see the platform's
[REST API reference](/docs/apis) and
[Subscribers overview](/docs/platform/subscribers). The Browser SDK
itself never creates or destroys Resources — it only authenticates
*as* one and consumes the Addresses the platform exposes to it.

## Reference

* [`SignalWire.user`] / [`SignalWire.user$`] — authenticated user
* [`SignalWire.directory`] / [`SignalWire.directory$`] — paginated address book
* [`SignalWire.preferences`] — per-client settings ([`ClientPreferences`])
* [`SelfCapabilities`] — per-call capability flags
* [`User`], [`Address`], [`Directory`] — the entity types

[`SignalWire.user`]: /docs/browser-sdk/v4/reference/signalwire/user$

[`SignalWire.user$`]: /docs/browser-sdk/v4/reference/signalwire/user$

[`SignalWire.directory`]: /docs/browser-sdk/v4/reference/signalwire/directory$

[`SignalWire.directory$`]: /docs/browser-sdk/v4/reference/signalwire/directory$

[`SignalWire.preferences`]: /docs/browser-sdk/v4/reference/signalwire

[`ClientPreferences`]: /docs/browser-sdk/v4/reference/client-preferences

[`SelfCapabilities`]: /docs/browser-sdk/v4/reference/self-capabilities

[`User`]: /docs/browser-sdk/v4/reference/user

[`Address`]: /docs/browser-sdk/v4/reference/address

[`Directory`]: /docs/browser-sdk/v4/reference/interfaces/directory