The letter is the quirky Q, and the subject is Quatrain
A Quatrain is a type of stanza, or a complete poem, consisting of four lines.
It appears in poems of ancient civilizations and continues into the 21st century
During Europe's Dark Ages, in the Middle East and especially Iran, poets such as Omar Khayam continued to popularize this form of poetry, also known as Ruba'i. There are twelve possible rhyme schemes, but the most traditional and common are AAAA, AABB and ABAB.
From the Rubaiyat
Come, fill the Cup, and in the fire of Spring
Your Winter garment of Repentance fling:
The Bird of Time has but a little way
To flutter - and the Bird is on the Wing.
or Gray's Elegy
The curfew tolls the knell of parting day,
The lowing herd wind slowly o'er the lea,
The plowman homeward plods his weary way,
And leaves the world to darkness and to me.
And then there is Christopher Marlowe's 'Passionate Shepherd to His love', and Sir Walter Raleigh's Reply....
John Donne got into the act too, copying shamelessly, but beautifully, from Marlowe's Passionate Shepherd
And you can too!! It may not have the elegance of Donne and Marlow or Omar Khayam, but
Roses are red
Violets are blue
Sugar is sweet
And so are You.
Visit here to find out more about Q, with thanks to Mrs. Nesbitt, Roger Green
and all their quaint and qualified helpers.