IRDs are popular with all financial market participants given the need for almost any area of finance to either hedge or speculate on the movement of interest rates.
The most basic subclassification of interest rate derivatives (IRDs) is to define linear and non-linear.
Linear IRDs are those whose net present values (PVs) are overwhelmingly (although not necessarily entirely) dictated by the one-to-one movement of the underlying interest rate index. Examples of linear IRDs are; interest rate swaps (IRSs), forward rate agreements (FRAs), zero coupon swaps (ZCSs), cross-currency basis swaps (XCSs) and single currency basis swaps (SBSs).
Non-linear IRDs form the set of remaining products. Those whose PVs are commonly dictated by more than the one-to-one movement of the underlying interest rate index. Examples of non-linear IRDs are; swaptions, interest rate caps and floors and constant maturity swaps (CMSs). These products' PVs are reliant upon volatility so their pricing is often more complex as is the nature of their risk management.
Further classification of the above is then made to define vanilla (or standard) IRDs and exotic IRDs. The categorisation of linear and non-linear and vanilla and exotic is not universally acknowledged and a number of products might exist that can be arguably assigned to different categories. These terms may also overlap.