A network protocol is a standardized set of rules that allows computers to communicate reliably across a network.
Below is a quick overview of eight core protocols that power the modern internet.
HTTP — HyperText Transfer Protocol #
HTTP is the foundational protocol of the web. It enables clients (usually browsers) to request and retrieve resources such as HTML pages, images, and APIs using a simple request–response model.
HTTP/3 — HTTP Over QUIC #
HTTP/3 is the next major evolution of HTTP, built on QUIC, a transport protocol running over UDP instead of TCP.
Benefits include:
- Reduced latency
- Faster connection setup
- Better performance on mobile and unstable networks
Bandwidth-heavy uses—like VR streaming—can significantly benefit from HTTP/3’s design.
HTTPS — Secure HTTP #
HTTPS adds TLS encryption on top of HTTP to protect data integrity and confidentiality.
It is now the default protocol for nearly all secure websites and applications.
WebSocket — Full-Duplex Real-Time Communication #
WebSocket enables two-way, always-on communication over a single TCP connection.
Unlike REST, where the client must “pull” updates, WebSocket allows servers to “push” data instantly.
Common use cases:
- Real-time chat and messaging
- Online gaming
- Stock/crypto trading dashboards
- Live collaboration tools
TCP — Transmission Control Protocol #
TCP provides reliable, ordered, and error-checked delivery of data across IP networks.
Most major application protocols (HTTP, SSH, SMTP) run on top of TCP thanks to its robust connection guarantees.
UDP — User Datagram Protocol #
UDP sends packets without establishing a connection, enabling low-latency communication with minimal overhead.
It does not guarantee delivery, but for time-sensitive data, speed is more important than reliability.
Typical examples:
- Voice calls (VoIP)
- Video conferencing
- Online streaming
- Real-time multiplayer gaming
SMTP — Simple Mail Transfer Protocol #
SMTP is the core protocol used to send and relay email between servers.
It typically works alongside IMAP or POP3, which handle mail retrieval on the client side.
FTP — File Transfer Protocol #
FTP allows transferring files between clients and servers using separate channels for:
- Control commands
- Data transfer
Although widely replaced by more secure options (e.g., SFTP, FTPS), FTP is still used in legacy systems and controlled environments.