How To Change the Author URL Slug in wordpress

Are you looking for a way to change the author URL slug? This snippet will change the default slug, mysite.com/author/name, to mysite.com/profile/name. However, you can change this to anything that you would like.
Instructions:

1. Add this code to your theme’s functions.php file or in site-specific plugin.
2. Change profile in line 4 to any name you would like.

add_action('init', 'cng_author_base');
function cng_author_base() {
    global $wp_rewrite;
    $author_slug = 'profile'; // change slug name
    $wp_rewrite->author_base = $author_slug;
}

Note: If changes is not reflecting after adding the code, you can check after updating permalink setting from back-end.

Add a custom class name to Wordpress body tag

Soution code for : Add a custom class name to Wordpress body tag

We can use the body_class filter, like so:

function my_plugin_body_class($classes) {
    $classes[] = 'foo';
    return $classes;
}

add_filter('body_class', 'my_plugin_body_class');

Although, obviously, our theme needs to call the corresponding body_class function.

What does apply_filters(…) actually do in WordPress?

Solution for : What does apply_filters(…) actually do in WordPress?

apply_filters($tag, $value) passes the 'value' argument to each of the functions 'hooked' (using add_filter) into the specified filter 'tag'. Each function performs some processing on the value and returns a modified value to be passed to the next function in the sequence.

For example, by default (in WordPress 2.9) the the_content filter passes the value through the following sequence of functions:

• wptexturize
• convert_smilies
• convert_chars
• wpautop
• shortcode_unautop
• prepend_attachment
• do_shortcode