He's asking about the taskbar
Yes, but there is the icon that is placed in the taskbar as a system icon, and the icon that is placed in the task bar as a short cut.
The system icon is the one that spins and changes colour when something is being scanned, and when right clicked on, shows a an Avast menu as per the attached screen shot.
If this icon is not being shown (in Windows 7) click on the show hidden icons, then customize, and set the Avast iconright to Show icon and notifications.
The form of the icon placed on the task bar as a short cut will depend on the "use small icons" setting for the task bar & start menu as shown in the jpgs from dprout69.