From Guild Wars 2 Wiki
A trophy is an item which generally drops from monsters. It can have one of several uses:
- Junk trophies are intended solely to be sold to an NPC. Some of them contribute to the Trash Collector achievement the first time they are acquired. Such items, which have no other useful purpose, will be automatically sold when you press the "Sell Junk" button on the NPC's Sell dialog.
- Salvage Item trophies can either be salvaged with a salvage kit to recover crafting materials, or sold to an NPC.
- Event item trophies are items which players have to collect during an event, then turn them in to an NPC to complete the event.
- Collection trophies are needed to complete many Legendary weapon/armor sets and have no residual value once received and added to the specific collection. Treat these as "participation" awards.
- Dungeon currencies, sometimes also referred as "dungeon tokens", are received mainly at the end of dungeons as both repeatable and daily bonus rewards. They can also be obtained from Bags of Wondrous Goods dropped by bosses within dungeons and from completing PvP reward tracks, and are used to purchase equipment from Dungeon merchants.
- Tokens are stackable items used as currencies in certain vendors. They are often received during Special events.