== LDS tabernacles? == 

 Three weeks ago, you helped answer my question on the Reference Desk about why the LDS Church builds more temples.  Could you help with another LDS question?  As I go through National Register of Historic Places lists for the western USA, I'm constantly running across various LDS tabernacles.  However, I'm confused: what makes a tabernacle a tabernacle?  In what way is it unique?  The relevant section of tabernacle says that it's a local gathering place and a worship center, but I'm unclear, for example, why locals couldn't gather at the meeting house for their ward.  Thanks for your help!