What is innobd? Is there any way to explain it to a internet dummy?
Okay, if you are familiar with spreadsheets, you know how you can label columns on a sheet and give them appropriate values for a given row?
You can think of that as a 'table' in a database.
In a relational database, of which SQL is a type of and MySQL is a specific software package that runs it, you allow values to reference others between tables... I am being very simplistic there, sorry.
In a 'true' SQL setup, these values are not allowed to get out of synch (amongst other things). However, this limits performance in some aspects, with certain limited benefits.
MySQL provides a number of 'database engines'. MyISAM, which does not hold to SQL's rules as tightly as it needs, is focused on speed, however there are locking issues - causing lag. Innodb follows SQL more completely, specifically involving row-level locking.
This means that, I have changed the engine so that when two people view topics at the exact same time, the lag will only occur if they are viewing the exact same thread...
...hope that helps : /