Microsoft is finally catching up to do-it-yourself ers by offering a downloadable version of Windows 7 for netbooks that can be put onto and installed from a USB drive. Removing the requirement of a DVD drive. The utility, Windows 7 USB/DVD Download Tool, simply creates a bootable USB drive from an .ISO file that can be bought and downloaded via the Microsoft Store. This feat has been around since the XP era and is now, in a sense, more legal.
The Windows 7 USB/DVD Download Tool can be downloaded here. Microsoft recommends at least 4GB of free space on the flash drive. Most netbooks face the upgrading problem because of the size, they lack the typical CD/DVD drive. Be sure however that your netbook can boot from a USB drive (most can).
Via [Computer World]