With App Engine, we can build web applications using the Python/Java programming language, and  our application runs on Google's scalable infrastructure, and uses large-scale persistent storage and services. The Python Runtime Environment App Engine includes a simple web application framework, called webapp, to make it easy to get started.App Engine supports Python 2.5. Our app take advantage of the many libraries, tools and frameworks for Python. The Development Environment We can develop and upload Python applications for Google App Engine using the App Engine Python software development kit (SDK).

MapReduce is a patented software framework introduced by Google to support distributed computing on large data sets on cluster of computers. The framework is inspired by the map and reduce functions in functional programming, although their purpose in the MapReduce framework is not the same as their original forms.

Google App Engine provides a Blobstore API that allows our app to serve 'Blobs' that are much larger in size say between 1 mb and 2 gb.Blobs are created by uploading a file through an HTTP request using a html form .When the form is submitted, the Google App Engine Blobstore creates a blob from the uploaded file returning the blob key that can be used to process the blob