Protocol Explorer is a free interactive network simulator: watch HTTP, HTTPS, TCP, TLS, DNS and 35+ protocols in motion, with every packet decoded byte by byte. Animated lessons are available in 8 languages. It is built for students, developers and anyone who wants to understand how the internet actually works. Key features: byte-level packet decoding, step-by-step animated protocol handshakes, 35+ protocols from DNS to TLS, no account required.