Curl

cURL connect URL : curl is a internet (data) transfer & testing tool
https://blog.logrocket.com/an-intro-to-curl-the-basics-of-the-transfer-tool/

• It supports various internet protocols of transfer, including:
  DICT
  FILE
  FTP, FTPS
  GOPHER
  HTTP, HTTPS
  IMAP, IMAPS
  LDAP, LDAPS
  POP3, POP3S
  RTMP, RTSP
  SCP, SFTP
  SMB, SMBS
  SMTP, SMTPS
  TELNET and TFTP
  the currentprotocols supported can be seen with : curl --version
• We can perform useful tricks with cURL like proxy support, user authentication, FTP upload, HTTP post, SSL connections, cookies, file transfer resume, Metalink, and more.
• curl is powered by libcurl for all transfer-related features.

curl -K : connect to a host or read a config file