Google Maps is a free desktop/mobile web mapping service developed by Google.
Google Maps offers dynamic satellite imagery (high-resolution imagery of cities mostly taken from satellites), street maps, panoramic views of streets (called Street View service: provides 360° panoramic street-level views of various locations), real-time traffic conditions (called Google Traffic: traffic data in real-time, using 4 coloured lines on the map as an overlay to display the speed of vehicles on particular roads), and route planning (called Google Driving Directions in the US.) for traveling by walk, car, bicycle, or public transportation.
Google Maps' satellite view is a "top-down" or "birds eye" view; most of the high-resolution imagery of cities is aerial photography taken from aircraft flying at 800 to 1,500 feet (240 to 460 m), while most other imagery is from satellites and is updated on a regular basis. Google Maps in combination with Google Street View, issues such as parking, turning lanes, and one-way streets can be viewed before traveling. Read more about Google maps here on Wikipedia.