Search engine optimization is constantly evolving. What worked and was accepted just a few years ago may be frowned on today.
Whether a particular tactic is acceptable, depends on why and how it's done.
For example, in the beginning guest blogging was considered a badge of honor because someone "thought your content was awesome enough or that you were important enough that they would republish something you wrote on their site."
Unfortunately, for some people guest blogging evolved into a quick way to 'earn' a backlink instead of a way to share quality content. Spammy content, disguised as a guest post, was everywhere. But perhaps because there were bloggers producing quality posts for other blogs, Google looked the other way. For awhile.
Then in January 2014, Matt Cutts said "stick a fork in it: guest blogging is done."
The online community set up such a hue and cry that Matt went on to clarify what he meant. Guest blogging in exchange for backlinks was frowned on, but guest blogging for good reasons such as exposure, branding and increased reach was still okay. The main focus seems to be why. Some of the things Google might look at to determine the intent of the post include:
- the quality of the post,
- whether it includes dofollow backlinks,
- plus perhaps the author having a history of doing many guest posts.
So some practices can be good or bad, depending on why and how. There are, however, some practices that are just bad. Some practices may be caused by inexperience. Other practices, like hiding text or buying links, can be someone's attempt to get better rankings with the thought it shouldn't be wrong because they aren't hurting anyone else.
Then there are practices that are immoral and sometimes just plain illegal. Check out the infographic below for more information. If you find it helpful, feel free to share it. Oh, and, may the force be with you!