You want a number of people to use WordSmith but aren't sure which licence type suits you.
There are 2 possibilities.
- NETWORK SITE LICENCE
- A BUNDLE OF INDIVIDUAL LICENCES
= one licence, one installation, numerous users
The main advantages are : cheaper, only one installation; the disadvantages
are: slower (network delays).
All you need is about 50MB of space on any shared drive which all your users can access (not a special dedicated server).
How it works : let's imagine a student at a PC and a network drive called N: at a given university. When the student runs N:\wsmith\wordsmith.exe, wordsmith first checks on N:\wsmith itself that the licence is valid; it then reads N:\wsmith\wordsmith.ini and finds out in that where individual settings for students should be read and written, usually a sub-folder of their My Documents called \wsmith or similar.
= one licence for each user 
The main advantages are : quicker, personal for the student/employee.
These licences can be time-limited by you using special extra software supplied and after the time limit is over the licences can be passed on to a fresh group of students.
No need to worry about the old students returning their licences because they expire naturally when you set them to.
The disadvantages are: more expensive, re-installation or upgrade on
multiple PCs.
Either way, the licence is valid forever and the software can be updated freely as often as you like while it still develops (ie. until there is a new major version).