I have a 320GB hard disk. I only use either ubuntu or kubuntu (12.04 for now). I don't want to use windows or any other dual boot os. And i need only 3 partitions on my hard disk. One for the OS and remaining two for data storage. I don't want to create swap also.

Now can i create all primary partitions on the hard disk. Are there any disadvantages in doing so. If all the partitions are primary i think i can easily resize partitions in future.

On second thought i have the idea of using seperate partition for /home. Is it good practice . If i have to do this, i will create 4 partitions all primary. In any case i don't want to create more than 4 partitions . And i know the limit will be 4.

So is it safe to create all 3 or 4 primary partitions. Pls suggest me, What are the good practices .

(previously i used win-xp and win-7 on dual boot with 2 primary partitions and that bugged me somehow i don't remember. Since then i felt there should be only one primary partition in a hard disk.)

EDIT 1 : Now i will use four partitions in the sequence - / , /home , /for-data , /swap . I have another question. Does a partition need continuous blocks on the disk. I mean if i want to resize partitions later, can i add space from sda3 to sda1. Is it possible and is it safe to do ?