Currencies are traded on the Foreign Exchange market, also known as Forex. This is a decentralized market that spans the globe and is considered the largest by trading volume and the most liquid worldwide. Exchange rates fluctuate continuously due to the ever changing market forces of supply and demand. Forex traders buy a currency pair if they think the exchange rate will rise and sell it if they think the opposite will happen. The Forex market remains open around the world for 24 hours a day with the exception of weekends.
The 109.02-146 is overhead resistance The USDJPY has waffled up and down today as the "market" digests overhead resistance at the 38.2% retracement of the move down from the April 24 high at 108.918 and swing resistance at 109.022 to 109.146. That area was home to swing lows going back to May. It was broken on May 31 and has not seen the levels since (see yellow area and red numbered circles).