Free software is a wide-spread type of software which is currently applied and used also in the Slovak Republic. Therefore an author who wishes to use his own software as free software should prepare the licence agreement in accordance with valid law and licensing conditions for free software. The concept of free software does not relate to the functional or technical characteristics of software, but it relates to the legal regime of this software. The author of the free software permits each user to use, make copies of and distribute free software, exactly or with changes, free of charge or for payment. The main purpose of free software is to maintain, protect and promote the freedom, to use, study, make copies of, modify and distribute software as well as to defend the rights of free software users.