Attention is big money on the web. Many people are making their living sharing and editorializing the things they find online. Your sophomore english teacher liked to see your sources, and we would too.
As far as I’m concerned, everything you post a link to should contain a via reference with two exceptions:
- You saw the linked content in your RSS feed, from performing a search, or navigating directly to the linked website by entering the URL.
- The person who provided you the link prefers not to be referenced or doesn’t have an address where you can send people their way (and even then, you could still give a shout-out).
Otherwise, there is really no excuse. You either followed a link on someone else’s site or twitter feed, or you were suggested through an email, SMS, or instant message.
Some people really count on that attention for their livelihood. You should give it to them.