If you can ‘like’ everything, do you value anything?

IN THE early 2000s, software developers at several different Internet startups more or less independently came up with ways for users to express approval (and in some cases disapproval) with minimal effort and – a big deal in those days of slow Internet connections – without having to reload the page.

At news aggregator Digg.com, every “digg” or “bury” helped determine which articles would be featured and which would not. Online community Everything2.com similarly used upvotes and downvotes, as well as a “cool” button labelled “C!”. Blog platform Xanga had an “eProps” button that allowed readers who didn’t want to leave a comment to at least acknowledge that they appreciated a post.

Review site Yelp aimed to reward users for reviewing restaurants and other businesses by having readers label the reviews “useful”, “funny” or “cool”. Video purveyor Vimeo set out to emulate Digg, but as a company executive later told Fortune, “we didn’t want to call it ‘Diggs’, so we came up with ‘Likes’.”