data-list-facet, data-facet-value and data-select-single understanding

Question

I am an android developer,trying to get started with web development. I have a filter which works in ajax-ish and displays the result. Please bear with me as I am a complete beginner.

Here is the code:-

 <?php foreach (array_keys($statuses) as $key): ?>
                        <?php
                        $status_name = $key;
                        $status_data = $statuses[$key];
                        ?>
                        <button class="btn btn-<?php echo $status_data['id'] ?> " data-list-facet="js-promise-status" data-facet-value="<?php echo $status_name ?>" data-select-single="true" style="background-color: <?php echo $status_data['color_bright'] ?>;  border-color: #333;">
                            <i class="fa fa-<?php echo $status_data['icon'] ?> fa-fw" aria-hidden="true"></i>
                            <span> <?php echo $status_name ?></span>
                        </button>
                    <?php endforeach; ?> 

My problem is: How are the data-facet-value,data-list-value and data-select-single working to fetch the results?

<button class="btn btn-<?php echo $status_data['id'] ?> " data-list-facet="js-promise-status" data-facet-value="<?php echo $status_name ?>" data-select-single="true" style="background-color: <?php echo $status_data['color_bright'] ?>;  border-color: #333;">

Note:- If it is unclear,just make a comment and I will complete it.