Codex Functions

wp_enqueue_style();
wp_enqueue_style(
string $handle,
string $src = ”,
array $deps = array(),
string|bool|null $ver = false,
string $media = ‘all’ )

wp_enqueue_script();
wp_enqueue_script(
string $handle,
string $src = ”,
array $deps = array(),
string|bool|null $ver = false,
bool $in_footer = false )

get_template_directory_uri();
Retrieve theme directory URI on functions.php).

echo get_template_directory_uri();
Retrieve theme directory URI static.