It's a tool for remote management of a computer, it's not a big security risk to keep it enabled, but it's not really needed on a home computer.
If you want to disable it then you can do so in the BIOS by switching the computer on and when you see the dell logo on the screen tap F2, once in the BIOS look under advanced settings and then look for intel active management and set it to disabled.
You can also stop the icon for it loading in windows by running MSCONFIG and unticking intel active management under the services and startup tab.



