The service includes two code pages: the first one allows to register the last visit of users to the website, and the second one allows data registration and showing number of active/online visitors in a period of time defined by the webmaster. No databases are used, and data is saved to files within a user defined folder. The activity of users is recorded to individual files (one empty file per users). The name of each file is the IP address of the users, and the last modification time of the file is used as reference for last visit of the user. When counting the number of active users, Filesystem Functions are used to check the files: old files are deleted and newer ones are accounted as active users.