Shards are virtual goods you can purchase and support your favorite streamers in the form of tips. Streamers identify their most enthusiastic and loyal fans by the amount of Shards received. In turn it allows them to acknowledge and show their appreciation to valued supporters either through a personalized message, shout outs, etc.
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If you wish to purchase some Shards to start tipping, you can do so by visiting: www.tipstream.razer.com