Servers don't exactly "speak" in the way humans do, but they use various protocols and languages to communicate and handle requests. Here are some key ones:

1. HTTP/HTTPS: These are protocols used for transferring web pages and data over the internet. When you access a website, your browser and the server use HTTP (HyperText Transfer Protocol) or its secure version, HTTPS.

2. TCP/IP: This is a fundamental protocol suite used for network communication. TCP (Transmission Control Protocol) ensures reliable transmission of data, while IP (Internet Protocol) handles the addressing and routing.

3. SQL: For database servers, SQL (Structured Query Language) is used to manage and query data in relational databases.

4. FTP/SFTP: File Transfer Protocol (FTP) and its secure version, SFTP (SSH File Transfer Protocol), are used for transferring files between servers and clients.

5. SMTP/IMAP/POP3: These are protocols used for email servers. SMTP (Simple Mail Transfer Protocol) handles sending emails, while IMAP (Internet Message Access Protocol) and POP3 (Post Office Protocol) handle receiving and retrieving emails.

6. REST/GraphQL: For APIs, servers might use REST (Representational State Transfer) or GraphQL to handle and respond to requests for data.

Servers use these protocols and languages to perform their tasks efficiently and communicate effectively with clients and other servers.