Ipod Touch 4G Multitasking Question

[[S]tormz]

Hi I'm new to these forums and just bought my iPod Touch 4G under a week ago.

In regards to the multitasking, when I open, say, safari, and press the home button once, does this mean it is still open and needs to be closed in the multitasking bar, or is this simply a shortcut to a recently used app? Will having many apps and menus open in the multitasking bar use my battery and/or CPU excessively?

[rackstar]

like with all computers, running tasks in the background will drain battery and eat cpu cycles. if the icon is in the multitasking bar, then the app is open/running.