PCDATA or parsed character data is a DTD schema representing an XML string that should be examined by the parser - i.e. it can be parsed as any unspecified element or string.
<!DOCTYPE buildings [
<!ELEMENT building (#PCDATA)>
]>
<building></building> ✅ valid
<building>Hamilton</building> ✅ valid
<building><house>14 Dawson Street</house></building> ✅ valid