Theme supports (theme_support) (tag)

add_theme_support()

Registers support for new theme features in WordPress (support for thumbnails, post formats, etc.).

current_theme_supports()

Checks if the theme supports the specified feature, registered via add_theme_support().

get_header_image()

Gets the URL of the header image, which is set in the theme settings.

get_header_textcolor()

Gets the text color for the header (title). The color is set in the theme settings if this option is enabled in the theme.

get_theme_support()

Gets the arguments of the specified feature that were passed when registering this feature for the theme (template).

has_header_image()

Checks if a header image is set for the site (custom header).

header_image()

Outputs the URL of the header image, which is set in the theme settings.

remove_theme_support()

Allows themes to cancel previously registered new features.