

In a cell church, the fundamental building block is the "cell group" -- a
small group of no more than 15 believers.  The small groups are responsible
for the ministry of the church: evangelism and discipleship.  The emphasis
is on relationships, not on programs, and both the evangelism and the
discipling are relationship-based.

This will probably raise more questions than it answered, but that's it in
a nutshell.