For External Hard, one partition is better Or multi-partitions?

Hi everybody

I bought WD MY Book 2TB

I want to use My book to archive my files (Most of my files is between 100MB ~ 2000 MB)

I want to know If I make multi-partitions is better or one partition?

I know If I want to install an OS on external hard, I must make at least two partitions (One for OS and Others for Data & files)

But If I want to use it for archive files and backup , What is the best?

Beacuse someones tell that for bakcup files (like archive videos) only one partition is better that multi-partitions , and it is optimize the performance of External Hard. (we can only use folders to arrange our files and multi-partitions is not neccessary)

And others tell that multi-partitions is better because it increase defregmant’s speed and you can seperate your files better (Those files that important to you in one partion and other files that you delete or change , in other partions)

And for that reason , I don’t know wiich way is best for my External Hard.

Can someone help me?


Most of these USB externals will not work as a bootable drive for an OS. 


I know that ( That is simple) … you didn’t get my real question

I don’t want to install OS on my external hard , It was only an example.

I asked if I use my external hard to take back up of my files , which one is better for external hard (like WD My book) : One partition or multi-partitions ?

A lot of people post and want to install the OS on the external drive.