The action hook to save post meta on is called:

How does one add a cron schedule recurrence?

WordPress supports many-to-many relationship by default.

Which define constant needs to be set in wp-config.php to Force SSL on the Admin Panel?

The mu-plugins folder in a WordPress install works only in WordPress MU (or Multisite)

If a file named 'plugin-install.php' is in your plugin folder:

You can create a custom post type:

What does the 'RPC' in name 'XML-RPC' stand for? ('XML-RPC' is used by WordPress to connect to external resources such as a mobile WordPress application)

which function is use for display usermeta information ?

How can you make your custom function my_function() pluggable?

What Filter Hook is used to modify the output of the_content()?