https://en.wikipedia.org/wiki/Delegate#Democratic_Party
The distinction I draw is that pledged delegates are chosen at the state or local level through caucuses and primaries. Like the caucuses or not, they are still a Democratic process that allows voters to assign delegates.
Superdelegates are not chosen by the voter. They are an insurance policy for the Democratic Party by assigning them to people with power to ensure that a candidate like Bernie Sanders, who rejects their system and structure of power, is never elected to be president. They stack the deck against him by publicly supporting Hillary,
giving her 15% of the delegates needed to win, two months before the races even started, which is then picked up by the media who make it look like she's already won because of the giant difference in delegates (she has 469 supers now). This skews the race enormously, a big reason why many people aren't voting for him is because they think he has no chance.
Rightfully complaining about the caucuses not being fair (and lets be honest, from both sides here, this entire primary process has been a disgrace to American Democracy) is not the same issue that I have with the Superdelegates. I hope that is clear now. Again, if it was up to me, everyone 18 and up can automatically vote, voting day is a national holiday and we have open primaries with same day registration in all 50 states. But these are two completely different issues.
