Arachne for DOS can be used with any 100% DOS compatible operating system, such as MS-DOS 3.3+, DR-DOS 7.0+, Windows 9x, ROM-DOS or PTS-DOS. 
Arachne for DOS will run on i8086 compatible CPU with as little as 475 KB of DOS memory (540 KB if you want PPP connection) and EGA or VGA video card. However, recommended configuration is PC with 80386 or better CPU with 4 (or more) MB of memory, more than 600 KB od DOS memory, 512 (or more) KB VESA compatible SVGA card, with mouse, soundcard and color monitor. If you want dial-up access to internet, you of course need standard serial modem; for local networks, you can use any device with packet driver available for it (eg. Ethernet card). You will probably like to download Arachne self-extracting distribution package using some networked PC (for example at some Internet cafe, using Netscape or MSIE) and store it to single floppy disk, for example as file named INSTALL.EXE. Older versions of Arachne used to be quite hard to install. Since Arachne 1.50 beta 2, all you have to do with the downloaded file is to execute it (eg. by typing a:install) and follow the instructions on the screen. (If you don't like self extracting installator, you can download traditional ZIP file isntead, and run setup.bat after unpacking it). 

When installation of Arachne is finished, type arachne command to start arachne - this launches arachne.bat. Largest executable in the package, file core.exe, is just one component of the browser, and can't be used standalone - this is not any kind of shareware restriction, this is simply only way to run Arachne, never mind registered or unregistered. 

Notes for advanced users: 

On computers which are not compatible with i386 (real or virtual machines), you have to apply package "16bit.apm" before visiting pages with JPEG or PNG images. You can do this by storing file "16bit.apm" to Arachne directory and typing "arachne 16bit.apm". 
If you are using DR-DOS 7.01, don't use DPMI memory driver supploed with this system! 32bit utilities DJPEG32 and PNG2BMP used by Arachne will load their own DPMI driver (CWSDPMI). DPMI support in DR-DOS 7.03 can be used without problems.