DR-WebSpyder is a DOS web browser, mail client and operating system runtime environment that was developed by Caldera UK[1] in 1997.

It was based on the DR-DOS operating system and networking components from Novell as well as the Arachne web browser by Michal Polák of xChaos software.

NIOS comprised 32-bit versions of Novell's existing 16-bit DOS technologies including the DR-DOS operating system, Novell's modem dialer and TCP/IP stack from LAN Workplace for DOS / NetWare Mobile plus licensed third-party components such as the Kaffe Java virtual machine (JVM), Allegro for graphics, and Mosaic for the web browser.

[clarification needed] Gross's plans were interrupted when Caldera, Inc. acquired the remaining Digital Research assets including DR-DOS from Novell on 23 July 1996, but without the personnel.

and TCP/IP stack,[6] added support for animated and scaled GIFs,[6] an optional on-screen keyboard for mouse and touch panel usage (SoftKeyboards) for possible keyboardless operation,[6] and an install program.

[16][17][13] This was in fact the DR-WebSpyder OS configured as loosely coupled components in which a special version of the DR-DOS ANSI.SYS driver would mute the stream of text messages at startup of the DOS system[nb 1] while a graphical company logo was displayed until the web browser was launched as a shell via CONFIG.SYS SHELL replacing the default COMMAND.COM command line interpreter.

[nb 2] On 386 PCs with a minimum of 4 MB of RAM,[7] the floppy would boot the DR-DOS 7.02 based browser operating system complete with memory manager, RAM disk, dial-up modem, LAN, mouse and display drivers and automatically launch into the graphical browser, without ever touching the machine's hard disk in order not to interfere with other systems installed on the machine and to demonstrate its potential usage in diskless workstations.

A further refined international revision of the demo by Matthias R. Paul utilized more sophisticated multi-level compression to free enough space on the floppy image to also include menu options and additional drivers to choose between several languages and keyboard layouts and give room for further expansion or customization of the operation system and browser through OEMs or users.

[28] Caldera's DPMS-enabled dynamically loadable LONGNAME driver provided VFAT-compatible LFNs in the FAT file system utilizing UCS-2 internally.