Options:

-o <file>    # --output: write to file
-u user:pass # --user: Authentication

-v           # --verbose
-vv          # Even more verbose

-I           # --head: headers only

Request:

-X POST          # --request

Data options:

-d 'data'    # --data: HTTP post data, URL encoded (eg, status="Hello")
-d @file     # --data via file
-G           # --get: send -d data via get

Headers:

-A <str>         # --user-agent
-b name=val      # --cookie
-b FILE          # --cookie
-H "X-Foo: y"    # --header
--compressed     # use deflate/gzip

SSL:

--cacert <file>
--capath <dir>

-E, --ecrt <cert>     # --ecrt: Client cert file
    --cert-type       # der/pem/eng
-k, --insecure        # for self-signed certs

Examples

# Post data:
  curl -d password=x http://x.com/y

# Auth/data:
  curl -u user:pass -d status="Hello" http://twitter.com/statuses/update.xml

# multipart file upload
  curl -v -include --form key1=value1 --form [email protected] URL