The term "Gatecamp" refers to a fleet whose purpose it is to intercept incoming and outgoing traffic through a gate.
A gatecamp within 00 space needs:
- at least two heavy interdictors (the more the better)
- a sizeable amount of interceptors for decloaking and tackling
- one covert-ops scout on the other side of the gate
- ships with a high damage output
This is the most basic setup. The more recon ships/interdictors you add to this basic setup the more success you'll have. The heavy interdictors might be replaced by mobile warpdisruptors but in doing so you sacrifice tactical flexibility.
Lowsec and highsec gatecamps need to rely on interceptors and heavy interdictors with the focused warpdisruption script since they are not allowed to use mobile warpdisruptors or warpdisruptprobes of any kind.
Highsec gatecamps usually consist out of a scanner scout, who searches for suitable targets, and a pack of insured battleships with a high amount of alpha damage. This tactic, among others, is also know as a suicide gank.