The right-hand side (literally the right of the two numbers) in a two-way price quote is the ask. It indicates the lowest price at which a dealer, investor or market maker is willing to sell at.
E.g. if AUD/USD = .9310/15, to take the right-side you would buy the AUD at .9315.
The difference between the left and the right hand side of a two-way price quote is the spread.