#### CD **CD** (for Change Directory) changes the current *drive* and/or *folder* (for *drives* that support *folders)* or current *drive* (for *drives* that do not). **CD**'s syntax is as follows: **CD** *filespec* where *filespec* consists of either one or two of the first two parts of a filename (*Drive* and *Folder*) for *filesystems* that support *folders* (*FAT16*, *FAT32*) or of just the *Drive* for *filesystems* that do not (*+3DOS*, *IDEDOS*). Setting just the *current drive* with **CD** is functionally equivalent to using **SAVE**, **LOAD** etc with just the *drive* as the *filespec*. Unlike *folders*, there is no way of setting a *user area* as the default one so if you need to address it you must do so explicitly through the *filespec;* for example add a **3m:** prefix to *filenames* for files in the *user area* **3** of drive **m:**. **CD** works with *wildcards* by matching to the first folder in order it finds them and change to that. **CD** also accepts three *filespec shortcuts*: **.** (single dot), .. (double dot) and one of the following / or \ (forward or backward slash). As we mentioned earlier in the chapter, single dot means: *This* folder, double dot means: The folder *one level up* and either slash on their own means: The *root folder* of the *current drive*. Single and double dot entries *do not exist* on the *root folder* and therefore you cannot use the *shortcuts* there. Using a combination of the double dot and slash *shortcuts*, **CD** can also easily traverse the folder tree horizontally at the same level without having to write the entire path that precedes the level you're currently in. Obviously that doesn't make sense at the first level under the root as it would involve much more typing than the slash character alone but it works nonetheless! Assuming a structure like the one in your **System/Next™** distribution as partly displayed in the figure below, lets provide some examples of horizontal and vertical navigation.  ``` System/Next™ example folder organisation / | +----------+---------+---------+ | | | nextzxos machines docs | +-------------+------------+ | | | dotcommands extra-hw cpm ``` *Fig. 21 – Folder tree navigation* Let's agree that we're located in the / of drive **c:** and we want to first go to **c:/docs/cpm** and then go to **c:/docs/extra-hw** before returning to / again. We could use one of the following sequences: ``` CD "docs" CD "cpm" ``` and then ``` CD ".." CD "extra-hw" ``` and finally