If you participate in Nightfall Strikes, Flashpoints, Lost Sector Chests, Raid Chests, Raid Encounters, Strike Bosses or Planetary Chests, you will be able to earn these items.
Dismantle exotic weapons and armor you don’t use and you’ll get 10 shards for each piece of equipment.
Disassemble legendary equipment you don’t use and you’ll earn 2 shards for each equipment.
There are several ways to win these special shards in Destiny 2, with some easier and more profitable ways than others, which you can read here: So it is a good idea to start accumulating these shards. Those who played the first Destiny know that Xur sold exotic equipment in exchange for Strange Coins, but now he will order Legendary Shards. The good news is that Xur will return on Destiny 2, and will appear randomly in public spaces at one of the four locations in the sequel and will sell exotic equipment. If you’re a Destiny fan, you know Xur, an NPC who sold exotic equipment on Destiny.