Serial (radio and television)
In television and radio programming, a serial has a continuing plot that unfolds in a sequential episode-by-episode fashion. Serials typically follow main story arcs that span entire television seasons or even the full run of the series, which distinguishes them from traditional episodic television that relies on more stand-alone episodes. Worldwide, the soap opera is the most prominent form of serial dramatic programming.
Television special
A television special (often TV special, or rarely "television spectacular") is a stand-alone television show which temporarily interrupts episodic programming normally scheduled for a given time slot. Specials have been produced which provide a full range of entertainment and informational value available via the television medium (news, drama, comedy, variety, cultural), in various formats (live television, documentary, studio production, animation, film), and in any viewing lengths (short films, theatrical films, miniseries, telethons).