> For the complete documentation index, see [llms.txt](https://docs.nats.io/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.nats.io/using-nats/developer/sending.md).

# Sending Messages

NATS sends and receives messages using a protocol that includes a target subject, an optional reply subject and an array of bytes. Some libraries may provide helpers to convert other data formats to and from bytes, but the NATS server will treat all messages as opaque byte arrays.

All of the NATS clients are designed to make sending a message simple. For example, to send the string “All is Well” to the “updates” subject as a UTF-8 string of bytes you would do:

{% tabs %}
{% tab title="Go" %}

```go
nc, err := nats.Connect("demo.nats.io", nats.Name("API PublishBytes Example"))
if err != nil {
    log.Fatal(err)
}
defer nc.Close()

if err := nc.Publish("updates", []byte("All is Well")); err != nil {
    log.Fatal(err)
}
```

{% endtab %}

{% tab title="Java" %}

```java
Connection nc = Nats.connect("nats://demo.nats.io:4222");

nc.publish("updates", "All is Well".getBytes(StandardCharsets.UTF_8));
```

{% endtab %}

{% tab title="JavaScript" %}

```javascript
const sc = StringCodec();
nc.publish("updates", sc.encode("All is Well"));
```

{% endtab %}

{% tab title="Python" %}

```python
nc = NATS()

await nc.connect(servers=["nats://demo.nats.io:4222"])

await nc.publish("updates", b'All is Well')
```

{% endtab %}

{% tab title="C#" %}

```csharp
// dotnet add package NATS.Net
using NATS.Net;

await using var client = new NatsClient(url: "demo.nats.io", name: "API Publish String Example");

// The default serializer uses UTF-8 encoding for strings
await client.PublishAsync<string>(subject: "updates", data: "All is Well");
```

{% endtab %}

{% tab title="Ruby" %}

```ruby
require 'nats/client'

NATS.start(servers:["nats://127.0.0.1:4222"]) do |nc|
  nc.publish("updates", "All is Well")
end
```

{% endtab %}
{% endtabs %}


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