This idea uses a small retaining wall to address a small slope from the house to the street. Whether natural or planned, it's smart to build your home elevated above the street for drainage and flood purposes. And actually, it's rare to see a home that doesn't take this into consideration. However, there are some out there.
In this example, the slope is minimal and could have easily been a gradual slope to the street without the terrace and retaining wall. However, this retaining wall idea is much classier, adds planting areas for curb appeal, and keeps the lawn area level for easier mowing and irrigation saturation. See watering on a slope.