Emacs/docs/latest/emacs/Enriched-Faces

From Get docs

25.14.4 Faces in Enriched Text

The following commands can be used to add or remove faces (see Faces). Each applies to the text in the region if the mark is active, and to the next self-inserting character if the mark is inactive. With a prefix argument, each command applies to the next self-inserting character even if the region is active.

M-o d

Remove all face properties (facemenu-set-default).

M-o b

Apply the bold face (facemenu-set-bold).

M-o i

Apply the italic face (facemenu-set-italic).

M-o l

Apply the bold-italic face (facemenu-set-bold-italic).

M-o u

Apply the underline face (facemenu-set-underline).

M-o o face RET

Apply the face face (facemenu-set-face).

M-x facemenu-set-foreground

Prompt for a color (see Colors), and apply it as a foreground color.

M-x facemenu-set-background

Prompt for a color, and apply it as a background color.

These commands are also available via the Text Properties menu.

A self-inserting character normally inherits the face properties (and most other text properties) from the preceding character in the buffer. If you use one of the above commands to specify the face for the next self-inserting character, that character will not inherit the faces properties from the preceding character, but it will still inherit other text properties.

Enriched mode defines two additional faces: excerpt and fixed. These correspond to codes used in the text/enriched file format. The excerpt face is intended for quotations; by default, it appears the same as italic. The fixed face specifies fixed-width text; by default, it appears the same as bold.