This description mentions some special things. Many of the things that are special to Windows apply also for the new Unix GTK version done by Eric Boucharé.
Euler uses a stack of fixed size. The stack contains all computed elements, and the local variables of the active functions. To set the stack size in Windows, use the menu. The new stack size will be effective at the next start of Euler. In Unix, use the command line option "-s" to set the stack size.
Graphics are stored in an internal format. The area used to store graphics is limited. You can change the size of this are in Windows with a menu entry.
There are two fonts. One for the text, and one for the graphis. In Windows, there is a comfortable dialog to edit both of these fonts. The fonts will be scaled with the graphics window size, if possible. In Unix, you will have to use the command line to choose a fixed font.
Euler uses 16 colors. In Windows, you can edit all colors with a menu entry. The first two should be black and white, since they are used for basic text output. Colors 2 and 3 are used most often, also for text output, and should be green and red. The option to use pure colors only is somewhat outdated, since most systems run on a real color basic now.
The Windows version can print graphics directly. It can also print a comment below the graphics. In Unix, it is best to save as postscript as described in the graphics section, and to print the postscript or use it in TeX.
In Windows, text, command and graphics can be saved to the clipboard. When saving text, there is a choice between commands and all text. Selecting text for the clipboard is done in the usual way by dragging over the text with the mouse. Commands can be used to generate an external Euler file. Graphics are copied in Windows Metafile Format.
Graphics can be saved as postscript by all versions of Euler. The procedure is described here. The Windows version can save graphics in Windows Metafile Format and in Bitmap format. In Unix, one can use the usual screendump features to get a dump of the graphics screen.
In Windows, the output of the Euler system can be deleted. This can either be done for the selected region, or for the complete file.