Does black hat techniques really affect on the website rankings?

[william17]

@bonnieshona Me and my co-workers operate tons of those sites. Which can be called as black hat. But hasn't gotten any penalty so far.

Just take an example say if your friend gives you a link. Then how Google is going to penalize it. Google will just probably won't know it.

As Zeus said, it's hard for Google to identify and penalize black hat techniques, and people do use such techniques every now and then. But one should be aware that these activities should not be done too often or on a large scale because if you do so, the chance of you getting caught by Google's algorithm increases and once you get caught, you are gonna penalized for sure and you website ranking will fall in the search engine results.