The covenant not to sue, which is an agreement by one party not to bring an action against the other party, either for a limited period of time, or not to bring it at all,1 has legal effects which in some respects are substantially the same as the effect of the sealed release, and in other respects are greatly different from those of the release.2 It is because of these resemblances that the covenant not to sue must be considered in connection with the release; and it is because of these differences that the two must frequently be distinguished.