To close the driver's stream, you will use a standard **CLOSE #** command (in the examples above that would be **CLOSE #8**). Once the driver's channel is open, you can use any of *NextBASIC*'s stream input, output or pointer manipulation commands (if these are supported by the loaded driver; Usually each driver's documentation should describe what can be used). A good example of using the driver channels can be found in the documentation for the ESP (WiFi) driver by Tim Gilberts, included in the **c:/docs/extra-hw/** folder of the **System/Next™** distribution. You can see there for example that talking to the internet via *NextBASIC* can be as simple as: ``` OPEN #4,"d>N>TCP,145.239.200.34:80" ``` which will open a TCP connection to port **80** on **specnext.dev** ### Windows *NextBASIC* offers the ability to create and manipulate text "windows" on screen via its Window Channels. This allows for immense flexibility in manipulating textual output, going beyond what simple **PRINT** commands can. #### System Windows vs User Windows When we talk about *Windows*, we're really talking about two kinds; *System* and *User Windows*. The former are created and managed by *NextBASIC* while the latter are created and controlled by the user. By default, 4 *System Windows* are created; one for each Layer other than 0. These are full screen and are used to produce output through the standard **s** channel and only a few parameters of these can change (size always remains the maximum possible).  ``` You can instantly 'wash' windows to new colours: Size 3 And if tYou can also save the to your contents of a window, in your owncase something overwrites it, and then restore it It is polater. 5 standard cursor-m 6 INK and more spe can be o 7 Block gr scaled t [graphic] but Size 8 to the current size. Press a key to continue ``` *Fig. 33 – NextBASIC Text Windows* *User Windows* on the other hand can have varying sizes and can be defined anywhere in the screen. From now on, we'll refer to System Windows as *SW* and to User Windows as *UW*. If no designation exists, then the discussion applies to both types. #### Defining User Windows User windows are defined by their top line (**0** to **23**), leftmost column (**0** to **31**), height (**1** to **24**), width (**1** to **32**), and optionally by character size (**3** to **8**) and character set memory address[^p214-6]. [^p214-6]: *Memory address refers to an address location within the main memory map.*