> For the complete documentation index, see [llms.txt](https://limitless.gitbook.io/ramm/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://limitless.gitbook.io/ramm/introduction/fixed-term-vs-perpetual.md).

# Fixed Term vs Perpetual

In RAMM, there are two types of instruments. For both these types a manager would purchase **`longZCB`** if he believes the underlying instrument would be profitable, but each has its own mechanism for realizing profit\&loss. 

1. Fixed-term & yield instruments are assets that have a set maturity and a predetermined rate for the capital it uses. An example would be a fixed-term loan. If a borrower requests 100k USD with 10% interest and agrees to pay it back in a year, the predetermined yield from lending out 100k is 10k. 

2. Perpetual instruments are assets that do not have a set maturity, and where the yield/returns can accrue in a perpetual fashion. An example would be supply positions to pool-to-peer lending pools with an ERC4626 standard, or asset portfolio constructions. 

More details on how the payouts for **`longZCB`** would differ are discussed [here](/ramm/prediction-market-and-amm-technical/tradable-tranches.md)