SQL Server Memory Clerk Description
There are 4 kinds of memory clerks in SQL Server. 


Generic
Cache Store
Object Store
User store


memoryclerk_sqlgeneral is a general memory clerk responsible for a variety of non-specific sql activities whereas the memoryclerk_sqlbufferpool is the clerk dedicated solely to the buffer pool, since the buffer pool is a busy process.

Links:

SQLServer-DBA memory

MSDN Memory Clerks