A cashier's check is not the same as a teller's check, also known as a banker's draft, which is a check provided to a customer of a bank or acquired from a bank for remittance purposes and drawn by the bank, and drawn on another bank or payable through or at a bank.
Microsoft Excel 2007, along with the other products in the Microsoft Office 2007 suite, introduced new file formats. The first of these (.xlsx) is defined in the Office Open XML (OOXML) specification.
DOCX is an MS Office text format of new generation (starting from 2007 versions). It is a more open, more standardized version that allows various apps get easier access to data stored in Word files. DOCX files are lighter in size than DOC analogues due to a new, XML-based file structure.