wordpress get archive title

-the_archive_title():
you can just use this one function to do the work of is_Category() and is_Author() functions automatically.
It displays the archive title based on the queried object. so you dont need to put the if and else conditions
for each archive title. it will simply get the archive title from the url based on the user selection. 

$archive_title = get_the_archive_title()

// * Filters the archive title prefix.
// apply_filters( 'get_the_archive_title_prefix', $prefix );

// * Filters the archive title.
// apply_filters( 'get_the_archive_title', $title, $original_title, $prefix );