Extras

Useful things that don't belong to any one topic.

Drag and drop — dragula.php
Using the Dragula library to make lists you can rearrange by dragging.
 Resizing images — convert.php
Making a thumbnail from an uploaded photo, so you aren't serving 20MB files.
 Sending email — sendingEmail.php
The mail queue pattern, and what you need to build. Shows its source rather than sending.
 Processing the mail queue — sendingEmailProcessDemo.php
A worked example of the sending half.