RúMIL

In J. R. R. Tolkien's legendarium, 'Rúmil' is a fictional character, a Loremaster of the Noldor living in the city of Tirion. The origin of his name is not clear, possibly deriving from the stem ''rum'', a secret.
Rúmil was the first Elf who invented writing: he invented the alphabet called Sarati (each letter being a ''Sarat''). This alphabet was later expanded and perfected by Fëanor as the Tengwar.
Rúmil was also a skilled linguist, and when the Teleri finally arrived in Valinor he was first to discover just how the Telerin language had changed from Common Eldarin compared to Quenya.
Rúmil was one of the Noldor who refused the summons of Fëanor, and he remained in Tirion as one of the Noldor of Finarfin, where he presumably remains still.
In The History of Middle-earth series, Rúmil is additionally given as the original author of much of the work which is included in ''The Silmarillion'': the ''Ainulindalë'', ''Valaquenta'' and ''Annals of Aman'' are by his hand. He is also given as the author of the ''Lhammas'' and ''Lhammasethen'', as well as the ''Ambarkanta''.
Non-canonical material in ''The War of the Jewels'' attributes to him a collection of sayings called ''i Equessi Rumilo''.
Pengolodh of Gondolin later continued and completed much of his work.
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A very much later 'Rúmil', brother of Haldir, was a Silvan Elf of Lórien.