Most retail Forex market makers permit 100:1 leverage, but also, crucially, require you to have a certain amount of money in your account to protect against a critical loss point. For example, if a $100,000 position is held in Eur/USD on 100:1 leverage, the trader has to put up $1,000 to control the position.

Indirect quotation: 1 home currency unit = x foreign currency units.

Because foreign exchange is an OTC market where brokers/dealers negotiate directly with one another, there is no central exchange or clearing house.