WordPress get Category id by name

By using following function you can get category id. Parameter for this function are category name

<?php $cat_id=get_cat_ID( $cat_name ) ?> 
/*
Parameters $cat_name=String category name
returns 0, if failure and ID of category on success. 
*/

Credits

Get Category Id By WordPress Codex
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WordPress Use shortcode outside post editor in theme files

WordPress added function called do_shortcode() using this function you can call wordpress shortcodes outside post editor and you can call shortcode in you wordpress theme .php files.

// Use shortcode in a PHP file (outside the post editor).
do_shortcode('[album]');

Credits

WordPress Functions
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