Most documents are also available as postscript files, primarily for easier downloading of multipage documents such as course notes. To view or print these files, you first need to download them to your computer and save them under a name you choose, such as "my_file.ps", for example. To download and save a postscript file, simply click on the relevant link and follow the dialog boxes that appear. To view a postscript file, you need a special viewer. On the Unix machines administered by the Department of Systems and Computer Engineering, such a viewer exists and is called "ghostview". Once you downloaded a postscript file and saved it under the name "my_file.ps" (for example), you can invoke the viewer on an X-Windows display with "ghostview my_file.ps". To print a postscript file from a departmental account, you typically need printer privileges on a postscript printer. Since I will make arrangements to have major documents copied for you (in 94.574 and 94.581, for example, the course material is available through the bookstore), I strongly discourage students from printing out pages and pages of material on the departmental printers. Should I receive complaints about the abuse of the laser printers, I will withdraw the files from the course pages.
To view and print postscript documents on MS-Windows (3.1, 95, 98, 2000, NT) machines, you often need to install an appropriate viewer yourself first. The most popular postscript viewer is called GSVIEW and can be found on many sites on the WWW. One example is Ghostscript, Ghostview and Gsview at the University of Wisconsin web server (which also includes the Unix version, ghostview). GSVIEW in turn requires the prior installation of GHOSTSCRIPT, so installation of these packages can take up quite a bit of diskspace. Once you installed GSVIEW on your machine, you can use the built-in print facility to either print the whole document or selective pages on a printer installed on your Windows system.
The larger documents are not stored in postscript format directly. These files are typically huge (multiple MegaBytes of data), so to reduce download times and diskspace on my webserver, I stored them in a compressed format, called gzip. To differentiate these compressed files from uncompressed postscript files, the former files have names that end with the suffix ".ps.gz" or ".ps.zip", while the latter have filenames that end with ".ps". So after you download these compressed files, you have to decompress them before you can view and print them. On the Unix machines, the relevant command is "gunzip", which will uncompress the file and strip the ".gz" or ".zip" suffix, leaving a file with only a ".ps" suffix. On MS-Windows machines, you again need to install a utility to uncompress gzipped files. Many useful utilities are available as shareware, for example from the WinFiles.com webpage for compression utilities.
I may make documents available as PowerPoint presentations or Word documents. The versions I am using as of July 2000 are the Office 2000 versions: PowerPoint 2000 and Word 2000, so you need the latest Microsoft Office packet (or the equivalent individual programs) to read these files. In some cases, your web browser will have plug-ins to automatically start up Word or PowerPoint. In other cases (if you run the web browser on a Unix machine in the department, for example), you can view the files by downloading them to a local disk or directory and transfering them to a PC using appropriate means.