Is Google Earth Engine API free?
Earth Engine is free for noncommercial use: learn more here. For commercial or operational applications, please click here to learn more about pricing options.
How far back will Google Earth go?
Google Earth's historical imagery tool combines data from many sources to show a particular area looked. You can go as far back as the 1930s. However, you can use the feature only on the desktop app, which may look a bit dated, but it has everything you'll need and then some.
What code is Google Earth Engine?
The Google Earth Engine uses the programming language JavaScript. Similarly to other programming languages, there is support online - you can google JavaScript and Earth Engine tutorials.