Claude Debussy

He first wrote it during the lean years after his return from Rome, and polished and published it only 15 years later. The title of the third piece, 'Clair de lune', comes from a poem by Verlaine, son-in-law of his childhood teacher Madame Mauté.

• The word 'bergamasque' comes from 'masques et bergamasques' in Verlaine's poem 'Clair de lune'. All four pieces, Prélude·Menuet·Clair de lune·Passepied, borrow the frame of old French dances, so the suite is best heard as a dreamlike recollection of 18th-century court dance.
• 'Clair de lune' begins very softly, with chords of paired notes descending slowly, the first beat left empty. Because the meter does not settle at once, the sound seems to hang in the air.
• In the middle section, the left hand spreads its chords one note at a time into flowing broken chords (arpeggios) that spread out like waves, while the right-hand melody floats above. This is the passage often likened to ripples glittering in the moonlight.
• Pianists differ so widely in tempo and hesitation in 'Clair de lune' that comparing great performances is a particular pleasure. The 1890 draft, meanwhile, does not survive, so how much was added in the 1905 revision cannot be known.

A regular at Mallarmé's Tuesday gatherings, he turned the poem's languid reverie into sound, and amid a broken engagement and poverty the piece first made his name widely known.

• The opening flute solo slides down by semitones and back again, and because its first and lowest notes lie an uneasy three whole tones apart (a tritone), it seems to belong to no settled key. This flute, beginning alone without accompaniment, is the breath of the whole piece.
• When the flute falls silent, the harp answers with a sound that slides as if sweeping down a keyboard (glissando), together with the horns. It is often read as the half-waking state of a faun drowsing in the summer noon.
• The flute theme returns several times, and each time the harmony beneath it changes. Follow how the same melody catches a different light.
• In the middle of the piece, a singing melody begun by the woodwinds and broadly taken up by the strings is the most ardent passage in the work.
• At the end, tiny cymbals no bigger than a palm (antique cymbals) ring out clearly, and the sound vanishes into the air. In 1912 the ballet Nijinsky made to this music caused an uproar with its sensual choreography.

His only completed opera, which he clung to for nearly 10 years, from his impoverished life with Gaby to his marriage to Lilly, and which, outlasting the jeers at its premiere and Maeterlinck's fury, made him famous overnight.

• At the opening of Act 1, the low strings sound slow, dark chords like an old church mode. They are often read as a forest where one has lost the way, and the frail melody that soon rises from the oboe points to Mélisande.
• The singers do not belt out arias but sing almost as if speaking, following the inflections of the French language. Listen to how each line of text is laid upon the notes.
• In the tower scene of Act 3, Mélisande sings 'Mes longs cheveux' unaccompanied at the window, and Pelléas buries his face in her cascading hair. It is the most famous scene in the opera.
• In Act 4, at the moment the two confess 'Je t'aime', the orchestra falls almost silent. This passage, which conveys the greatest emotion with the smallest sound, epitomizes the opera.
• The orchestral interludes between scenes were hastily lengthened just before the premiere, because there was not enough time for the scene changes. Today they are counted among the richest orchestral passages in the opera.

The work was completed during a stretch in which his marriage collapsed, Lilly's tragedy unfolded and his friends turned their backs on him. Despite a cool reception at its premiere, it became his signature orchestral work.

• The three movements are titled 'From dawn to noon on the sea', 'Play of the waves' and 'Dialogue of the wind and the sea'. At the opening of the first movement, the harp sounds above long-held notes in the low strings and the timpani, and the sea wakes out of darkness.
• The passage at the end of the first movement where the brass rings out in majesty sounds like the light of noon. Satie is said to have joked that he particularly liked the bit at about a quarter to eleven.
• In the second movement the harp, a keyboard of steel bars (the glockenspiel) and the triangle glitter like spray, and the meter changes often. Listen while picturing waves that break without any fixed pattern.
• He struck a trumpet fanfare from the middle of the third movement after publication, though some conductors restore it. It is a passage that often comes up when great recordings are compared.

A suite dedicated to his three-year-old daughter Chouchou, its playful piano miniatures hold the domestic warmth he found at the end of the scandal.

• The first piece, 'Doctor Gradus ad Parnassum', borrows the name of an old book of piano études to tease a child worn out by finger exercises. Listen for the way it slows in the middle, drifts into daydreams, then scrambles off again in a hurry.
• The second piece, 'Jimbo's Lullaby', was written for Chouchou's toy elephant. Its slow tread in the low register and its five-note tune built mostly on the black keys (the pentatonic scale) sound like a drowsy elephant.
• The fourth piece, 'The Snow Is Dancing', repeats the same figure without pause, painting snow falling ceaselessly beyond the window.
• The sixth piece, 'Golliwog's Cakewalk', romps along in the offbeat rhythm of the American cakewalk dance (ragtime), then halfway through borrows the opening chord of Wagner's 'Tristan und Isolde'. He marks the spot 'with great emotion' and at once answers it with a comic figure, mocking the Wagner he had once worshipped.

Twelve pieces written in the year his debts and illness began, they are the piano works that best reveal his idea of letting the sound be heard first and the title be learned later.

• The titles are attached at the end of each piece, in parentheses and followed by an ellipsis. The way of listening truest to the composer's intent is to hear each piece without looking at the title, notice what comes to mind, and then check it against the title.
• No. 2, 'Voiles', is written entirely in the whole-tone scale, in which every step is exactly the same, so it seems to hang in the air like sails suspended over a windless sea. For a moment in the middle it shifts to a five-note scale on the black keys alone, and a single gust of wind blows.
• No. 8, 'The Girl with the Flaxen Hair', is a brief, simple song that takes its title from a poem by Leconte de Lisle, and it is the best loved of the whole set.
• No. 10, 'The Sunken Cathedral', depicts the cathedral of Breton legend that sinks beneath the water and rises again. Above very low, bell-like notes, great chords move side by side at a fixed distance, ringing out like ancient chant.
• In the 'Sunken Cathedral' that Debussy himself recorded on a reproducing piano roll in 1913, he plays certain passages twice as fast as the score indicates. Performers still disagree over whether this points to a problem in the notation.

A sonata by the 'musicien français', written at Pourville in the summer of a year of war, illness and the loss of his mother, it compresses a longing for eighteenth-century French music into little more than twelve minutes.

• The three movements are 'Prologue', 'Sérénade' and 'Finale'. The stately piano chords at the opening of the Prologue recall the solemn beginnings of French music in the age of Couperin and Rameau.
• In the 'Sérénade' the cello mixes in a technique of plucking the strings with the fingers instead of the bow (pizzicato), sounding like a guitar or mandolin. He is said to have once considered the subtitle 'Pierrot angry with the moon'.
• The Sérénade runs straight into the Finale without a break. The passage where the lively Finale sinks midway into a slow, dreamlike reverie is the secret heart of the piece.
• Because it is short and free of excess, cellists differ in their interpretations according to how delicately they handle the color of each note and the length of each silence.