Placemarks[]
Placemarks are the most commonly used way of showing information in Google Earth.
Information[]
If you want to pinpoint your home, or another cool location, just use the "Add Placemark" button (in GE4 (Beta) it is the second button in the top bar) or press Ctrl+P. Add a title and a discription and you're done.
You can also choose an icon of your choice by clicking on the current icon at the top right, and then selecting your own. You can also choose a style and colour for the icon and title of the placemark.