docs(en): write introduction and getting-started pages

docs/en-US/getting-started/connecting.md

@@ -1 +1,77 @@
 # Connecting to a server
+
+termscp can start in three different ways depending on the arguments you pass.
+
+- No arguments: termscp opens the authentication form, where you provide the
+  parameters required to connect to the remote host.
+- An address argument: termscp skips the authentication form and connects
+  directly to the remote host.
+- A bookmark name with `-b, --address-as-bookmark`: termscp resolves the
+  argument as a saved bookmark and connects.
+
+When you provide an address argument or a bookmark name, you can also provide a
+start working directory for the local host.
+
+## The authentication form
+
+When termscp starts without an address, it shows the authentication form. Fill
+in the protocol, address, port, username, and password, then connect. termscp
+will open the dual-pane explorer once the connection succeeds.
+
+## Address argument syntax
+
+The generic address argument has the following syntax:
+
+```txt
+[protocol://][username@]<address>[:port][:wrkdir]
+```
+
+This syntax is convenient, and you will probably use it instead of the
+interactive form. Here are some examples.
+
+Connect using the default protocol (defined in your configuration) to
+`192.168.1.31`. If the port is not provided, the default port for the selected
+protocol is used. The username is the current user's name.
+
+```sh
+termscp 192.168.1.31
+```
+
+Connect using the default protocol to `192.168.1.31` as user `root`:
+
+```sh
+termscp root@192.168.1.31
+```
+
+Connect using SCP to `192.168.1.31` on port `4022` as user `omar`:
+
+```sh
+termscp scp://omar@192.168.1.31:4022
+```
+
+Connect using SCP to `192.168.1.31` on port `4022` as user `omar`, starting in
+directory `/tmp`:
+
+```sh
+termscp scp://omar@192.168.1.31:4022:/tmp
+```
+
+For protocol-specific address syntax (S3, Kube, WebDAV, and SMB), see
+[Connection parameters](connection-parameters.md).
+
+## How the password is provided
+
+When you provide the address as an argument, there is no field for the password
+in the address itself. You can provide the password in three ways:
+
+- You will be prompted for it. This is the default: if you don't use any of the
+  methods below, termscp prompts for the password, like classic tools such as
+  `scp` and `ssh`.
+- `-P, --password` option: pass the password directly on the command line. This
+  method is discouraged because it is insecure: the password may be kept in
+  your shell history.
+- Via `sshpass`: provide the password through `sshpass`, for example:
+
+  ```sh
+  sshpass -f ~/.ssh/topsecret.key termscp cvisintin@192.168.1.31
+  ```