Here’s a complete list of “Order” and “Order By” Parameters that can be used. When combining parameters, separate them with an “&” character.
https://codex.wordpress.org/Class_Reference/WP_Query#Order_.26_Orderby_Parameters
Common Examples
Most Recent Post to Oldest
order=DESC&orderby=date
Oldest Post to most Recent
order=ASC&orderby=date
Random Order
orderby=rand
Alphabetical by Post Title, from A-Z
order=ASC&orderby=title
Reverse Alphabetical order by Post Title, from Z-A
order=DESC&orderby=title
Order by Most Recent Modified
orderby=modified