An intangible property right
that can be enforced through court
action. (constrast negotiable instrument
An example of such a chose would be a copyright or the right to receive the monies from a pension. For most practical purposes, that's all you need to know.
There is no particular formality for the transfer of a chose in action, with the proviso that legal choses (transferable under statute law) must have their transfer evidenced in writing. The rule is that once the transferror has done all that he can to effect the transfer, the transfer is complete. Once the chose has been assigned, the recipient can sue upon it in his own name. In the past, the donor of the chose would have to be joined as either a plaintiff or defendant to the action, but no longer.
Certain rights are not assignable, specifically the proceeds of government pensions, and personal contracts. Personal contracts are defined in this sense as contracts where the personality of the party that would assign the chose matters to the other party to the contract.