The Professional Edition of Strawberry Prolog is our higher edition which includes all facilities and tools. The main advantage of the Professional edition comparing the Middle one is the possibilities to create Prolog CGI scripts and to build EXE files. These EXE files are very small but they need an installation of the Light Edition of Strawberry Prolog for work. This cannot be a problem because this edition is very small in size and it is free.

Professional edition of Strawberry Prolog is not freeware. If you want a password for it then you have to buy a license. We offer a subscription for all versions including 4.0. Now the price for this is $249 USD and we offer a student discount which is $119 USD.
 

The Middle Edition of Strawberry Prolog have complete functionality except creating of Prolog CGI scripts and EXE files. Like the Professional edition it is not freeware. You have to buy a subscription for it (which include all versions including 4.0). There will be a second possibility to obtain the middle edition. We will give it as a shareware for one month evaluation period together with the CD of some computer magazines. If you obtain the Middle edition from computer magazine then you have right to use it only for one month and only this version which is on the CD.

Now the price for subscription for the Middle edition is $98 USD and we offer a student discount which is $49 USD.
 

The Light  Edition of Strawberry Prolog is free but to download and use its last version you have to open an e-mail box at SecondBox.net. This is free e-mail box through which you will forget what SPAM was! This is more than just a free service. You will make money of it rather than to pay for it.

If you do not want to open Second Box address then you can download the previous version of Strawberry Prolog Light absolutely free and without any registration.