Sq, Sql?

wats SQ and SQL stand for?(researchin on RE subs and came across this, and yes im a noob)

adn wats ported? obviously "sealed" is a sealed enclosure with no holes, so would a ported enclosure have a hole?

SQ - sound quality, a system that reproduces the music as it was originally intended
SPL - sound pressure level, a system that gets really loud at one frequency and sucks donkey balls everywhere else
SQL - a system that sounds good and gets loud, not as loud as an SPL system and doesn't normally sound as good as a SQ system, but it's a nice mix of the 2

sealed - http://edesignaudio.com/Products/13Kv2Subwoofer/BoxDesigns/idealsealed.gif

ported - http://edesignaudio.com/Products/13Kv2Subwoofer/BoxDesigns/idealvented.gif