Install for each one. When the installation is complete, click  Finish

xxviii
Introduction
Setting Up Your Virtual Machine
Now let’s get you started with your virtual machine. VirtualBox should open 
once it has installed—if not, open it—and you should be greeted by the 
VirtualBox Manager, as seen in Figure 4.
Figure 4: The VirtualBox Manager
Since we will be creating a new virtual machine with Kali Linux, click 
New
in the upper-left corner. This opens the Create Virtual Machine dialog 
shown in Figure 5.
Give your machine a name (any name is okay, but I simply used Kali) and 
then select 
Linux
from the 
Type
drop-down menu. Finally, select 
Debian 
(64-bit)
from the third drop-down menu (unless you are using the 32-bit 
version of Kali, in which case select the Debian 32-bit version). Click 
Next
, 
and you’ll see a screen like Figure 6. Here, you need to select how much 
RAM you want to allocate to this new virtual machine.
Figure 5: The Create Virtual Machine dialog
Figure 6: Allocating memory

Introduction
xxix
As a rule of thumb, I don’t recommend using more than 25 percent of 
your total system RAM. That means if you have installed 4GB (or 4096MB) 
on your physical or host system, then select just 1GB for your virtual machine, 
and if you have 16GB on your physical system, then select 4GB. The more 
RAM you give your virtual machine, the better and faster it will run, but 
you must also leave enough RAM for your host operating system and any 
other virtual machines you might want to run simultaneously. Your virtual 
machines will not use any RAM when you are not using them, but they will 
use hard drive space.
Click 

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