Adobe Creative Cloud is expensive (roughly $55/month for the full suite). If you are a freelance copywriter, a project manager, or a student who has received an INDD file, you cannot open it without a subscription. Online converters allow you to extract the text and layout without paying for Adobe.
If you are a freelancer dealing with client INDD files, here is two pro-tips: indd to idml online converter
AConvert is a no-frills tool. It is not great for complex graphics, but if you just need to get the text out of a locked INDD file to paste into Word, it works instantly. Adobe Creative Cloud is expensive (roughly $55/month for