Character entity references can also have the format &name; where name is a case-sensitive alphanumeric string. For example, Î» can also be encoded as &lambda; in an HTML document. The character entity references &lt; , &gt; , &quot; and &amp; are predefined in HTML and SGML, because, ,  and & are already used to delimit markup. This notably does not include XML's &apos; (') entity.
Lack of facial expression. Lack of facial expression: Introduction. An absence of expression on the face is medically called flat affect. In many cases, the face mirrors the underlying emotions, and the person has limited emotions or various emotional or psychological disorders.
Offhand, you might guess ten, or twenty, from fear to disgust to sadness to joy to skepticism. But researchers now say that human faces might only be able to make four universally recognized facial expressions. For a while, researchers thought that there were six faces that everybody in the world could identify: happiness, sadness, fear, anger, surprise and disgust.