From EVE University Wiki
Filaments are items which can instantly transport a ship or a small fleet. There are four types of filament, with quite different effects and uses:
- Abyssal filaments transport pilots to a randomly-chosen pocket of Abyssal Deadspace, where they will face difficult time-limited PvE combat challenges with potentially lucrative rewards.
- Needlejack filaments transport pilots to randomly-chosen parts of nullsec space (“Noise” filaments) or randomly-chosen parts of nullsec space with high capsuleer activity (“Signal” filaments).
- Pochven filaments transport pilots either to a randomly-chosen part of Pochven, or from Pochven into a randomly-chosen part of lowsec or highsec space.
- Proving grounds filaments transport players to the Abyssal Proving Grounds for PvP challenges against randomly-chosen opponents, with ship and equipment restrictions.
Although they differ considerably in their destinations, all types of filament are alike in including an element of randomness.