The dictionary definition of the verb 'to redact' is 'to make ready for publication; edit or revise'.
In the media firestorm surrounding UK politicians and their expenses, 'redaction' refers to the deleting of any detail whatsoever that could possibly lead to controversy, leading to the comical situation in which, in the name of transparency, MPs' expenses claims are being published with all detail that could be sensitive or embarrassing completely blacked out. Comical example below.

In contrast, our new receipts functionality allows users to attach receipts electronically in almost any file format, including jpeg and other image formats (such as a digital photo taken with a mobile phone), PDF (the format that usually results when receipts are run through a scanner), HTML (such as a web page or email confirmation) and even Word or Excel.
The example below is a digital photo taken with my mobile phone and attached to my most recent expense claim.
