Terrorist organizations use the Internet to spread extremist ideas and recruit people in a variety of ways, mainly including the following aspects: 1. **Social media platforms**: Terrorist organizations use social media (such as Twitter, Facebook, Telegram, etc.) to publish propaganda materials, spread extremist ideas, and attract followers. Through various forms such as videos, pictures and text, the emotional resonance of the audience is deepened. 2. **Online forums and chat rooms**: Some extremist organizations establish communities in specific forums and chat groups to encourage communication and ideological collisions among members. These platforms provide a relatively safe environment for potential members to express their views freely and be recognized. 3. **Video sharing websites**: Through YouTube and other video platforms, terrorist organizations release extremist propaganda films, lectures and training videos to attract and influence young people. The video content usually contains themes such as armed struggle and heroism to stimulate the audience's emotions and desire to participate. 4. **Encrypted communication tools**: Terrorist organizations use encrypted communication applications (such as WhatsApp, Signal, Telegram, etc.) to communicate secretly and organize activities. These tools protect their privacy and make recruitment and organization activities more covert and secure. 5. **Online games and virtual worlds**: Some organizations reach out to young people through online games or virtual communities, using the common interests of players to establish connections, thereby spreading extremist ideas in a subtle way. 6. **Propaganda websites and blogs**: Extremist organizations may also set up their own official websites or blogs to publish manifestos, statements and propaganda materials, provide ideological training, and attract more followers. 7. **Using hot events**: Terrorist organizations often use social hot spots and political events for propaganda, using these events to arouse people's dissatisfaction and anger, thereby attracting potential supporters. 8. **Cultivating followers**: Through one-to-one communication and interaction, terrorist organizations can have a deeper understanding of the psychology and needs of potential members, provide emotional support and a sense of belonging, thereby enhancing their identification with the organization. Due to the anonymity and extensiveness of the Internet, terrorist organizations are able to effectively expand their influence and recruit more members. This poses many challenges to governments and relevant agencies in combating extremism. In response to this problem, countries have taken a variety of measures, including monitoring and intervening in online activities, strengthening online education and anti-extremism propaganda, etc.