Adding the “sortable” class to a <table> element provides support for sorting by column value. Clicking the column headers will sort the table rows by that column’s value. Tables must use <thead> and <th> tags for sortable functionality to work.
This is a copy and paste of the snippet google shows from https://www.bu.edu/tech/services/cccs/websites/www/wordpress... if you search for “sortable table”. The page is actually talking about how to author pages on their Wordpress site, which presumably uses a wordpress plugin to provide the JavaScript necessary to make this work.
Adding the “sortable” class to a <table> element provides support for sorting by column value. Clicking the column headers will sort the table rows by that column’s value. Tables must use <thead> and <th> tags for sortable functionality to work.