Here is a neutral and interesting 1-paragraph summary of the text: To send a picture on WhatsApp from the command line using Twilio and cURL, one needs to first set up a Twilio account and install cURL. A WhatsApp sandbox is then created, allowing for testing with a smartphone. Credentials are stored in environment variables, including the sender's phone number, recipient's phone number, and media URL. With these variables set, a command is used to send a picture message using cURL, which can be done on both Unix/MacOS and Windows computers. After sending the message, one can test their application with additional smartphones by repeating the sandbox registration process.