I have one of your fonts which is a shareware version. If you have one of these fonts and wish to use it you should register it. Registering a font is essentially the same thing as buying the font. You use our online system or call us, or send in a payment for the appropriate font or the package it is part of and that gets you the current version which will have characters and features missing from the shareware version. At that point your obligation is discharged.
Postscript fonts consist of two files, a screen font and a printer font.
As it is used today it is a format developed by Adobe and adopted by other font foundries. It is used primarily by high-end imagesetters who prefer it because the relationship between screen image and printed output is more reliable. In most cases you need Adobe Type Manager to use Postscript fonts effectively. TrueType fonts consist of a single file which contains both the screen and printer versions of the font. It is a format developed jointly by Apple and Microsoft as an alternative to Postscript.