When first connecting to the Internet you have to specify which programs you want to grant access to. What is very helpful in this software is that you can ask for more information and Zone Alarm will tell you what program is associated with the .exe attempting to gain access, along with a recommendation. Once you have your primary programs configured (and configuration is easy), everything else is seamless.
I am very very pleased with the ease of setup and integration of this software with my antivirus program. I would recommend this product any day over Norton's firewall or Internet security programs.
Well, you might ask, "So what? A firewall is supposed to block things like that." Yes, that's true, but ZAP continually asks for permissions. Annoying? Hardly. It lets you know that it is doing the job. You can mark a popup to set it so that program can always access the internet, or you can let it access the internet for only that time, or vice versa. Think something is running in the background and slowing your computer by constantly connecting to the internet?
Chances are that is possible. It was for me. I had a lot of programs connecting to the internet that definitely should NOT have been doing so. Zone Alarm Pro 4 gave me that window and, without knowing what the program was, inspected it further. Long story short - it never happened again.
It keeps a continuous log and permission screen so you can examine/change anything. It keeps a running counter to let you know how many intrusions ZAP has blocked since the installation.
The only problem with ZAP is that it might be too confusing for those without any computer experience. However, it is a necessity and is a MUST. Security is vital.