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