The use of the Internet makes up the everyday life of high school students, and they spend most of their time on social networks. They have open profiles on social networks that they use to communicate with other people as well as to share various content. In order to stay safe while using the Internet, they must have sufficient knowledge and skills on how to protect their data and privacy on the Internet. The aim of this thesis was to gain insight into the experience of high school students in the Split-Dalmatia County regarding the use of the Internet and social networks, especially in the areas of security, privacy and communication on the Internet. 21 students participated in this qualitative research, and the data was collected through focus groups. The first research question sought to find out how high school students describe communication in the online environment. The participants mentioned the challenges they face when communicating online and pointed out that it is more difficult for them to recognize sarcasm, irony, humor and the true meaning of the sent message. The second research question examines how high school students describe safety and privacy on the Internet and how they ensure their own safety and privacy on the Internet. The obtained results showed that high school students are considered safe Internet users and that they are aware of all the risks that its use entails. They are certainly familiar with ways to protect themselves in the online environment and most use them. The third research question examines the challenges that high school students recognize when achieving security and privacy on the Internet. High school students stated that they encounter threats, insults, fake profiles, but also that they are aware of the digital trail that is left when using the Internet.