A computer terminal and a method for blocking the use and transmission of vulgar and pornographic material in a responsive and interactive manner that comprehensively monitors computer operations for creation or transmission of vulgar and pornographic material. Data created by the keyboard, data passing through the clipboard, data selected by the mouse pointer, and data passing through the Internet interface are monitored for content and further operation of the computer terminal is blocked. The computer terminal may only be unblocked by a supervisory intervention, such as by entering of a password, or by restarting or resetting the terminal. Key word searches, such as those in Internet search engines, are also monitored, but the terminal adapts to monitor not only for words of a profane and vulgar nature, but also for words that are behaviorally tested to produce lists containing vulgar and profane items, e.g., Internet sites. The computer terminal and method can be modified to block other forms of communication or computer operation, such as blocking transmission of secret business data, blocking execution or opening of certain programs or files, and the like.