GBP/JPY is the amount of JPY exchanged for one GBP. The pound sterling is the UK's currency. Bank of England policy, domestic inflation and growth, and international financial activity shape demand.
Comparing charts on this board
Compare GBP/JPY with GBP/USD and USD/JPY to separate sterling's dollar leg from the yen leg. Moves in the same direction reinforce; opposing legs offset.
EUR/JPY distinguishes broader European-currency moves from sterling-specific ones. An isolated pound move directs attention to UK rates and releases; shared cross-yen movement directs attention to Japan.
Related charts: GBP / USD · USD / JPY · EUR / JPY
Official references: RBA: exchange-rate conventions