Microsoft is releasing its latest operating system Windows 10 on 29th july 2015.its currently under development but the most important question is will you be able to upgrade to windows 10 for free? or you’ll have to buy product or license key for windows 10.
below provided flowchart is the answer to this question.
Who is eligible to download windows 10 for free ?
if you have original windows 7 or windows 8 / 8.1 you can get free upgrade to windows 10.
but if you are using windows XP or vista you’ll have to buy windows 10.pirated version’s of windows also cannot be upgraded (officially).