Just like we did some weeks ago with MS Office we share here a list of official URLs to download the ISO images of the most recent versions of Windows OS: Windows 7, Windows 8.1 and Windows 10.
Don't worry, this is not warez or pirate software: all of these URLs come from the official Microsoft installation tools or are a link to download the tool itself. This also means that if you want to activate the software after installing it you still need to purchase a valid Product Key (not included) from the Microsoft Store or from any official reseller.
If you already own a valid Product Key you can simply visit this URL and pick one of the many Windows 7 editions available: Home Basic, Home Premium, Professional o Ultimate (32 bit or 64 bit), shipped with all the most recent updates and Service Packs.
If you don't have it yet you can either visit this page (softlay.net), where you can find most of the Windows 7 ISOs for free, or jump to the end of this post and use the Windows and Office ISO Download Tool.
Luckily enough all the Windows 8.1 ISO images - for Standard, Professional or Enterprise versions, 32bit or 64bit - are freely available from Microsoft thanks to their Windows 8.1 Media Creation Tool, which can be used to create your own installation media using either a USB flash drive or a DVD:
The tool is dead simple to use, however if you have issues you can check this official guide or (even better) take a look to this awesome guide from the guys of winsupersite.com.
The path to download the ISO images of Windows 10 (all versions) is almost identical to the Windows 8.1 one: all we have to do is to visit this page:
And download the appriopriate Media Creation Tool, which can be used to create your own installation media using either a USB flash drive or a DVD.
Windows and Office ISO Download Tool
In case we don't want to waste the handful of seconds which is required to use the Media Creation Tool, there's a third-party application containing the underlying TechBench links to the ISO images: its name is Microsoft Windows and Office ISO Download Tool and it can be downloaded for free from the author's page at HeiDoc.net.
That's it for now: happy download!