• Virtual computers act just like physical computers, without the hardware.computers network image by Orlando Florin Rosu from Fotolia.com
  
  Virtual PC software allows a user to replicate a computer environment without the use of additional hardware. Businesses use virtualization to create virtual data centers at a fraction of the cost of a physical data center. Home users can use PC virtualization to create separate virtual PCs for family members so each person can have their own computer.
  
  

Processor and Memory

• Virtual PCs can mimic various hardware configurations, but a user still needs to consider the hardware limitations of the host machine running the virtualization software. For optimal performance, the host machine should have a powerful processor and a good amount of RAM.
  
  A good rule to follow is to have the virtual machine run at 50 to 75 percent of the host machine's actual hardware. If the host machine has a 2.0 GHz processor and 4 GB of RAM, the virtual machines can be configured to emulate computers with up to 1.5 GHz processors and 2 GB of RAM.
  
  

Hard Drive

• The size of a virtual PC file determines how large the virtual hard drive on the virtual PC is. Users can choose to allocate all the space at once or have space dynamically allocated, where the initial file is small but expands to the indicated amount.
  
  Whenever possible, run virtual machines on a local hard drive rather than off of a network drive or an external hard drive. Hard drive speeds can affect the virtualization experience, and accessing a virtual PC from either the network or external drive can result in a less responsive virtual PC.
  
  

Networking

• Virtual PCs have the option of either emulating a network adapter or using the host computer's network adapter. When making the decision on which option to use, consider the purpose of the virtual PC. If the virtual PC requires its own IP address, emulating a network adapter is the best option. If the virtual PC is to be used simply for non-network software testing or another purpose that does not require its own IP address, using the host's network connection is the best option.
  
  

Limitations

• Virtual PCs can be used for tasks such as testing software, operating environments and basic Internet usage. It is not advisable to use virtual PCs for more hardware-intensive operations, such as graphics or video editing and gaming. These types of tasks on an emulated environment are more taxing to the host system and may not run as smoothly as on a physical computer.