i am guessing that the word 'extended' is a another word for logical.
Nope. An Extended partition is a Primary partition that creates a wrapper for the Logical partitions. You can only have one Extended partition per physical disk but you can have many Logical partitions within that Extended partition.
For multi-user systems or systems with lots of disk space, it's best to put /usr, /var, /tmp, and /home each on their own partitions separate from the / partition.
You are free to do whatever you want of course but all of my systems are multiuser and I have one partition for the OS that contains all of those directories ( / ), a swap partition, and a /Data partition.
There is some debate amongst users about the necessity of a separate /home partition. The argument for such a thing is that it contains not only the saved data but all the settings and tweaks you have made. If something goes wrong and you have to reinstall or when you upgrade all of those settings are preserved.
The argument against a separate /home partition uses those same facts in reverse. If something went wrong it's no doubt something in that users configuration that's the cause so you don't want to just bring it back. And if you upgrade you certainly don't want the old configurations since they may not even be applicable to the new versions of the software.
Anyway, I personally don't use a separate /home partition.