There are some function are listed which is commonly used in WordPress.
wp_nav_menu() : Displays a navigation menu.
is_page() : to check if this is page OR NOT, will return Boolean value.
get_the_excerpt() : Copy the excerpt of the post into a specified variable.
in_category() : Check if the specified post is assigned to any of the specified categories OR not.
the_title(): Displays the title of the post in website.
the_content(): Displays the contents of the post in website.
