Mautic is a widely used open source email marketing automation application written in PHP. Email marketing is typically used in conjunction with inbound marketing done by asking people to give their email address in exchange for something, like a free ebook or a newsletter with good content. As you’re asking for the email address on a publicly facing webpage, spambots will find your form, and start misusing it to send your “Welcome” emails all over the place. This in turn may result in lots of bounces and/or complaints, which may get you locked out from your email service provider unless you pay attention. So, you need a way to block or fool those spam bots to prevent such issues, and to keep the Mautic database clean.