Debian partitions

Setting up a Debian system, I have /dev/hda with the following

partitions:
 1 /      123.38 MB
 2 /usr  1126.87 MB
 3 /home 2401.79 MB
 4 ?
 5 /swap   65.81 MB
 6 /tmp   148.06 MB
 7 /var   501.75 MB
 8 /work 2130.35 MB

Partitioning seems to have skipped assigning /dev/hda4.

Q1: Is this significant?

I've seen references to a partition called /boot.
My understanding is that the whole system can
be a single partition if I wish, so I presume
/boot can be a mount-point within the root partition.

Q2: Do I need to do anything about /boot, or should
it just appear?

Vic