The inherit keyword specifies that a property should inherit its value from its parent. So if the h1 tag below lives inside a div element with its text color set to red, the color of the h1 text will also be red.

h1 {
    color: inherit;
}

The initial keyword is used to set a property to its default value (the browser default). So if you’ve changed the color of the h1 tags somewhere in your cascade of styles (perhaps a linked style sheet further up the list of style sheets), but now want to reset them to the default, “initial” is used.

h1 {
    color: initial;
}

The unset keyword resets a property to its inherited value if the property naturally inherits from its parent. If it doesn’t naturally inherit, it will set the property back to the initial value (browser default).

h1 {
    color: unset;
}