Medieval common law courts could award damages, and little else, through rigid procedural forms. Petitioners who needed something different — stop this, undo that, make him keep his promise — went to the Lord Chancellor, whose Court of Chancery decided by conscience rather than writ. Over centuries those decisions hardened into their own system: equity.
Equity gave the tradition trusts, injunctions, specific performance, rescission and fiduciary duties. Since the nineteenth-century Judicature reforms, the same courts administer both law and equity — but the two remain distinct bodies of doctrine, and equitable remedies remain discretionary in a way damages are not.
Canadian courts administer law and equity together, and Canadian equity has been notably creative — the Supreme Court's fiduciary-duty jurisprudence, including the Crown's fiduciary obligations to Indigenous peoples, is a distinctly Canadian development.