# Connecting to a Specific Server The NATS client libraries can take a full URL, `nats://demo.nats.io:4222`, to specify a specific server host and port to connect to. Libraries are removing the requirement for an explicit protocol and may allow `demo.nats.io:4222` or just `demo.nats.io`. In the later example the default port 4222 will be used. Check with your specific client library's documentation to see what URL formats are supported. For example, to connect to the demo server with a URL you can use: {% tabs %} {% tab title="Go" %} ```java // If connecting to the default port, the URL can be simplified // to just the hostname/IP. // That is, the connect below is equivalent to: // nats.Connect("nats://demo.nats.io:4222") nc, err := nats.Connect("demo.nats.io") if err != nil { log.Fatal(err) } defer nc.Close() // Do something with the connection nc = Nats.connect("nats://demo.nats.io:4222"); ``` {% endtab %} {% tab title="Java" %} ```text Connection nc = Nats.connect("nats://demo.nats.io:4222"); // Do something with the connection nc.close(); ``` {% endtab %} {% tab title="JavaScript" %} ```javascript let nc = NATS.connect("nats://demo.nats.io:4222"); nc.on('connect', (c) => { // Do something with the connection doSomething(); // When done close it nc.close(); }); nc.on('error', (err) => { failed(err); }); ``` {% endtab %} {% tab title="Python" %} ```python nc = NATS() await nc.connect(servers=["nats://demo.nats.io:4222"]) # Do something with the connection await nc.close() ``` {% endtab %} {% tab title="Ruby" %} ```ruby require 'nats/client' NATS.start(servers: ["nats://demo.nats.io:4222"]) do |nc| # Do something with the connection # Close the connection nc.close end ``` {% endtab %} {% tab title="TypeScript" %} ```typescript // will throw an exception if connection fails let nc = await connect("nats://demo.nats.io:4222"); // Do something with the connection // Close the connection nc.close(); ``` {% endtab %} {% tab title="C" %} ```c natsConnection *conn = NULL; natsStatus s; // If connecting to the default port, the URL can be simplified // to just the hostname/IP. // That is, the connect below is equivalent to: // natsConnection_ConnectTo(&conn, "nats://demo.nats.io:4222"); s = natsConnection_ConnectTo(&conn, "demo.nats.io"); if (s != NATS_OK) // handle error // Destroy connection, no-op if conn is NULL. natsConnection_Destroy(conn); ``` {% endtab %} {% endtabs %}