O through Z
O P Q R S T U V W Y Z
Obbligato: an occasional but extended instrumental
solo, often to accompany the vocal part in an aria.
Octave: the interval between two notes six whole
tones apart that bear the same name; thus, C natural
to C natural. An augmented octave is C natural to C
sharp; a diminished octave, C natural to C flat.
Octet: a work for eight instruments.
Ode: a formal celebratory address to a person or on
the subject of an abstract quality. There are several
examples by Purcell, and the form was revived by
Schoenberg and Stravinsky in this century.
Open strings: the strings of a stringed instrument
when played without being fingered.
Opera: a drama in which the actors sing and are
accompanied by an orchestra. It was invented at the
beginning of the 17th century in Italy as a court
entertainment by composers such as Monteverdi, who
were attempting to revive classical Greek drama. By
the end of the century it became a widespread public
entertainment. In the first half of the next century, in
the works of Handel and Alessandro Scarlatti, it was
characterized by spectacle and vocal virtuosity. In the
reforming spirit of Gluck and the operas of Mozart
that followed, a new simplicity and psychological
penetration entered into opera. In the 19th and 20th
centuries, opera has been written by practically every
major composer, and, in the hands of Wagner.
became the focal point of some of the most advanced
musical thinking of the day. Opera continues to
fascinate composers, despite the complexity,
difficulty, and expense of mounting new works.
Operetta: a light and perhaps short opera, often
comic, usually with spoken dialogue instead of
recitative. There are familiar examples by Jacques
Offenbach, Johann Strauss, Arthur Sullivan, Franz
Lehdr, and Sigmund Romberg.
Opus: literally, a work; shortened to Op., a
convenient method of numbering a composer's
works. Thus, Beethoven's Op. 111 is his last
Oratorio: an extended cantata on a sacred subject,
such as Handel's Messiah, Mendelssohn's Elijah, or
Sir William Walton's Belshazzar's Feast.
Orchestra: a large group of instrumentalists, at least
some of whom are normally playing more than one to
a part. Chamber orchestras may have only twenty
players, but a large symphony orchestra may consist
of more than a hundred players. The basic
instruments that make up its regular membership
have remained constant since the late 18th century,
although the orchestra since then has been increasing
steadily in size. Instruments are occasionally added
and ultimately become a fundamental part of the
orchestra. The clarinet was added in the last years of
the 18th century; the trombone in the first years of the
19th; then the tuba, the harp, numerous percussion
instruments, and so on.
Ornaments: formalized decorations of a melodic
line, such as the trill or the mordent.
Ostinato: a repeated phrase.
Overture: an extended prelude to an opera also, the
term for a Baroque suite or an independent orchestra]
work, often on a literary theme. There are examples
of the latter by Tchaikovsky, Berlioz, Elgar, and
Pariando: a rhythmically free or even semi-spoken
way of singing.
Parody: as in "parody mass," a work based on
previous material, one of the three common
techniques of composition in medieval and
Renaissance sacred music.
Part: an individual voice, or instrument, in a piece;
or a line in a contrapuntal work.
Partial: a harmonic given off by a note when it
Partita: a Baroque suite of dances, adapted by Bach
as a suite for keyboard instruments.
Part-song: an unaccompanied vocal work in
Pasodoble: a fast 1920s dance in 6/8 time.
Passacaglia: a set of variations over a repeating
bass; virtually identical to the chaconne, but with a
theme rather than a chord sequence in the bass. There
is a celebrated example by Anton Webern.
Passe-pied: a French Baroque dance in triple time.
Pastorale: a theatrical piece, song, or instrumental
piece on a pastoral theme or idyllic in character.
Pause: a held note, or a moment of silence.
Pedal: the foot-operated mechanisms on piano,
organ, or timpani; also, the term for a long-held bass
Pentatonic scale: a five-note scale on which much
folk music is based: the most common corresponds to
the black keys on the piano.
Phrase: a single line of music, usually played or
sung by a single musician in one real or metaphorical
Piano: instruction to play softly, abbreviated p; more
quietly, pianissimo, abbreviated pp.
Pitch: the frequency of a note; how high or deep it
Piu: more (for example, piu mosso, "faster").
Pizzicato: of stringed instruments, plucked rather
Plainchant: unaccompanied church singing.
Poco: little (for example, poco a poco crescendo,
"getting louder little by little").
Polka: a fast 19th-century middle-European dance in
Polonaise: heroic or ceremonial Polish dance in
triple time, transformed in the examples for piano by
Chopin into a kind of ceremonial rhapsody.
Polyphony: the art of counterpoint, or combining
Polytonality: the combination of two or more keys
simultaneously. Twentieth-century music has often
used the technique-for instance, the simultaneous
sounding of C major and F sharp major in Stravinsky's
ballet Petrushka, or many examples by Milhaud.
Portamento: a mild glissando between two notes for
Prelude: a short piece, originally preceding a more
substantial work, for instance Bach's Preludes and
Fugues; also, an orchestra] introduction to an opera
not substantial enough to merit the term overture, or a
short independent piano piece, often collected into
sets, such as those by Chopin, Debussy, and
Presto: tempo marking, meaning "very fast."
Program music: music on a particular non-literary
subject, usually with a narrative-for instance, some
of Couperin's keyboard works, or Richard Strauss's
Progression: a series of harmonies.
Punk: a fiery, high-speed variant of rock that values
excitement and energy above technique.
Quadrille: a French 19th-century dance in duple
Quadruplet: a group of four notes played in the
time normally occupied by three.
Quarter note: a note equal in time value to two
eighth notes or four sixteenth notes; in Britain, it is
called a crotchet.
Quartet: a work for four instruments, such as a
string quartet, consisting of two violins, viola, and
cello or, in opera, an ensemble for four singers.
Quasi: almost (for example, quasi forte, "almost
Quaver: the British term for an eighth note.
Quintet: a work for five instruments, such as a
string quintet, consisting of two violins, two violas,
and one cello, or two violins, one viola, and two
cellos, or a wind quintet. for flute, oboe, clarinet,
bassoon, and horn.
Quintuplet: a group of five notes played in the time
normally occupied by three or four notes.
Quodlibet: a medley, or a polyphonic combination
of well-known tunes.
Raga: an ancient traditional melodic pattern or mode
in classical Indian music; also, an instrumental
improvisation based on a traditional raga, in which a
melody is usually played over a pedal note without
change of key.
Ragtime: a style of music with a characteristic
syncopation in duple time, predating jazz but sharing
some of its characteristics. Its most famous composer
was Scott Joplin. Igor Stravinsky wrote two
compositions based loosely on the style, Ragtime and
Piano Rag Music.
Rallentando: getting slower.
Rap music: a form of pop music based on chanted
street poetry and rhymes accompanied by a thumping
Recital: a concert by a soloist, with or without
accompaniment. The term was invented by Liszt for
his solo performances.
Recitative: a form of vocal writing in opera or
concert works close to the manner of speech. It is
rhythmically free, and simply accompanied either by
a sinale keyboard instrument or by a small group of
instruments. By the Classical period it had become
a means of conveying information rapidly about the
narrative, while arias and ensembles evoked the
emotional states of the characters in a more expansive
manner and a more complex musical style. In the
19th century, the distinction between recitative and
melodic forms diminished, and in the operas of
Wagner, the vocal style might be said to move freely
between the styles of recitative and aria. Since then,
recitative has been occasionally used for special
purposes, as in Stravinsky's The Rake's Progress and
Reed: in wind instruments, the piece of cane that the
player causes to vibrate by blowing through it, in
order to produce sound.
Reel: i Scottish or Irish folk dance in duple time.
Refrain: a repeating phrase that occurs at the end of
each verse in a song.
Reggae: Jamaican popular music, associated with
Rastafarianisni, which achieved great popularity in
the United States and Europe in the 1970s.
Register: a portion of the range of an instrument or
voice; thus, the bottom octave of the clarinet is
known as the chaltimeau register.
Relative major and minor: the major and minor
keys that share the same key signature. Thus, E major
is the relative major of C sharp minor, since both
have four sharps.
Relative pitch: the ability to determine the pitch of a
note in terms of its relationship to the notes that
precede and follow it.
Repeat signs: the signs at the beginning and end of a
section of music, indicating that the section in
between should be played twice.
Reprise: a repeat of some earlier material. generally
after some different music has intervened.
Requiem: a mass for the dead in the Roman
Catholic liturgy, although works that are not settings
of the mass text may also be called requiems, such as
those by Brahms, Delius, and Hans Werner Henze.
Resonance: the phenomenon by which several
strings tuned to pitches that are harmonically related
will vibrate even if only one of the strings is struck.
Thus, if a note is struck on a piano, with the strings
undamped, the strings tuned to pitches that belong to
the harmonic series of that note will also vibrate.
Rest: a period of silence within a piece of music.
The various lengths of rests correspond to note
Rhapsody: a musical composition of irregular form,
and having a dramatic, improvisatory character,
usually either for a solo performer or a soloist
Rhythm: the element of music pertaining to time
and expressed as grouping of notes into accented and
unaccented beats, of beats into measures, etc.
Ricercar: an elaborate polyphonic or imitative
instrumental composition of the Renaissance or
Riff: a repeating motif or refrain in a modern pop
song or jazz piece.
Rigaudon: a fast 17th-century dance in duple or
quadruple time, of French origin.
Pitardando (ritenuto) - slowing down, perhaps for
less time or less forcefully than would be implied by
Ritornello: a passage that returns repeatedly in a
rondo-like form-. also, a tutti passage in a concerto.
Rococo: a short-lived musical style that occurred
roughly between the end of the high Baroque and the
beginnings of the Classical period, most often applied
to the music of such French composers as Couperin,
Claude Daquin, and Rameau. Often characterized as
trivial, ornamental, or lightweight, it is sometimes
called the gallant style.
Rondo: a musical form in which the principal
theme is repeated several times, with short sections
based on different themes (called episodes) in
between each restatement of the opening theme;
sometimes one or more of the episodes is also
repeated, a common pattern being ABACABA. The
rondo was often used for the final movements of
Classical sonata-form works.
Root: the principal note of a triad or triad-derived
Round: a canon in which the melody is sung by two
or more voices in strict imitation (i.e., using the same
notes) of the original statement, and in which all the
parts repeat continuously. (See Canon.)
Rubato: literally, "robbed." A style in which the
strict tempo is temporarily loosened by either speed-
ing up or slowing down.
Rumba: a lively Cuban dance, in quadruple time,
divided into a characteristic 3 + 3 + 2 pattern of
Saltarello: a fast Italian dance in 6/8 time.
Samba: a fast, syncopated Brazilian dance in duple
time, based on an Afro-Brazilian ring dance.
Sarabande: originally a fast triple dance, by the
17th century it had become a grand slow dance,
regularly featuring in Baroque dance suites.
Scale: the successive notes of a key or mode.
Scat singing: a style of jazz singing with nonsense
syllables, popularized by Cab Calloway in the 1920s.
Scherzando: jokingly, or in scherzo style.
Scherzo: a fast movement in triple time that
replaced the minuet in sonata-form works from the
beginning of the 19th century on. Unlike the minuet,
it was never a dance, and is generally faster and
more elaborate in structure, replacing the ABA of
the minuet with an ABABA form. Later, scherzi
were written as independent works, by Chopin and
Scordatura: retuning the strings of a stringed
instrument, either to obtain notes ordinarily below the
range of the instrument (Berg wrote B naturals below
the lowest C for the violoncello in his Lyric Suite) or
to produce an unusual tone color (the solo violin in
Mahler's Fourth Symphony is retuned up a whole
tone to harshen its sound).
Score: the full copy of all notes to be played in a
musical work. This may be in the form of a large
"full score," or a reduced "miniature score," or a
"vocal score" for use in rehearsal (with instrumental
parts reduced to a piano part).
Seguidilla: a fast Spanish dance in triple time.
Semibreve: the British term for a whole note.
Semiquaver: the British term for a sixteenth note.
Semitone: normally, the smallest notated pitch
difference in Western music-for instance, G to G
Sempre: always, or still (for example, sempre piano,
Senza: without (for example, senza sordo, "without
Septet: a composition for seven players.
Sequence: a successive transposition and repetition
ol' a phrase at different pitches.
Serenade: a somewhat lighthearted piece, either a
song or an instrumental work in several movements,
such as those by Mozart, Brahms, or Schoenberg.
Serial music: a way of writing music in which
unity is supplied by basing the entire composition
on a short series of notes in which no pitch is
repeated until all are used once. Invented by Arnold
Schoenberg in the 1920s as a way of ordering atonal
music, the series originally consisted of the twelve
tones of the octave (called a tone row). The series
may be transposed to any other pitch, may be played
backward, in inversion, or backward and in inversion
to generate forty-eight separate forms from a single
series. Schoenberg's pupils Alban Berg and Anton
Webem refined the technique. Webem worked with
series divided into three or four identical segments, to
give the illusory sense that the work is written on a
three- or four-note series. Berg used more than one
series in each piece; in his opera Lulu. each character
is identified by a particular series. In later
developments, after World War 11, Olivier Messiaen
extended the technique to apply to non-pitch
elements such as rhythm and dynamic levels; and
Igor Stravinsky, in his late works, often used series
of fewer than twelve notes.
Sextet: a work for six players (for example, a
string sextet, consisting of two violins, two violas,
and two cellos).
Sforzando: a strong accent; written
Shake: a trill.
Shanty: a sailors' song.
Sharp: a sign indicating that the pitch of a note
should be raised by a semitone.
Siciliano: a fairly slow dance with swaying rhythm
in compound time, usually 6/8 or 12/8.
Skiffle: hybrid of folk music and jazz played on
improvised, nontraditional domestic instruments,
such as washboards, jugs, etc.
Slide: a glissando or portamento; or the moving part
of a trombone.
Slur: a curve over notes to indicate that a phrase is
to be played legate.
Sonata: an instrumental work for a soloist or two
players. In early examples by Domenico Scariatti.
the piece is in one movement, but in general a sonata
is in three or four movements. The first movement
is generally in sonata form, followed by a slow
movement. In a four-movement sonata, the third
movement is usually a scherzo or minuet (although
sometimes this is the second movement, preceding
the slow movement). The sonata ends with a more
extended last movement, usually at a fast tempo.
This is the structure that many sonatas follow,
although the departure of many of Beethoven's
piano sonatas from the model suggests its limitations.
Sonatas have been written more or less constantly
from the late 18th century onward, and are still
being written; there are distinguished examples by
such contemporary composers as Pierre Boulez,
Jean Barraque, and Elliott Carter.
Sonata form: the musical form that evolved in the
later years of the 18th century, used in almost every
large-scale work-symphonies, quartets, piano
concertos, and even ensembles in operas-well into
the 19th century and beyond. Sonata form refers
primarily to the organization of themes and harmonic
relationships within a single movement, the general
structure of which consists of an exposition, a
development section, and a recapitulation. The
exposition (which may be preceded by an
introduction, usually in a slow tempo) presents the
primary themes in the main key and a second group
of themes in a subordinate key or keys, and a partial
developments the entire exposition may be repeated,
perhaps in different form (for instance, in a concerto,
the exposition mav be played first by the orchestra
alone and then again with a soloist). In the
development section, any portion of one or more
themes from the exposition may be presented with
new or related material in any order and in any
combination, moving through different keys but
eventually returning to the original key of the
movement. The recapitulation sets out the themes
ol'the exposition in the same order as the exposition,
but in somewhat different form, such as presenting
both the primary and second group of themes in the
main key; a short concluding passage, called a coda,
may follow. This three-part structure is also known
as ABA form. The sonata form lasted so long and
produced so many masterpieces principally because
it was capable of great variation.
Sonatina: a short sonata, sometimes with the
implication that it is not too difficult to play, such as
those by Muzio Clementi; there are also elaborate
examples, not for beginners, by Maurice Ravel, Jean
Sibelius, and, most notably, Ferruccio Busoni.
Song cycle: a sequence of songs, perhaps on a single
theme, such as Mahler's Kindertotenlieder, or with
texts all by one poet, for instance Debussy's Fetes
Galantes, or having a continuous narrative, such as
Soprano: the highest female voice.
Sordino: a mute.
Sostenuto: sustained, often with a suggestion of
playing quietly or more slowly.
Soul: the pop refinement of church-based, African-
American gospel music.
Soundboard: the part of a piano that amplifies the
Spiccato: a type of bowing on stringed instruments
in which the bow is allowed to bounce rather than be
drawn across the string.
Staccato: abbreviated and detached notes.
Staff: the horizontal lines on which notes are set
down; in modem notation, there are five lines on
Steel band: an ensemble of beaten oil drums, played
like tuned percussion instruments, originating in the
Stop: a device that controls the different sets of
pipes (or strings) for each note on an organ (or
harpsichord), enabling the player to temporary
change the tone color.
Stretto: in fugue, the overlapping of the same theme
or motif by two or more voices a few beats apart;
also, more loosely, an accelerando, with the
suggestion of an approaching close.
Suite: a loose collection of instrumental pieces. In
the Baroque period, a collection of dances as in
B.ich's instrumental and orchestral suites; in the 19th
and 20th centuries, a series of character pieces, as in
Holst's suite The Planets, or a set of excerpts from i
larger work, e.g., the suites from Grieg's music for
Peer G.Ynt or Ravel's Daphnis and Chloe suites.
Swing: a form of big-band jazz, popular in the 1930s
and '40s. with a strong element of massed effects and
less improvisation than in earlier forms of jazz.
Symphonic poem: a single-movement orchestral
work with a narrative or a literary theme. Invented by
Franz Liszt. it was taken up by such composers as
C6sar Franck and, most notably, Richard Strauss,
whose lonu and complex symphonic poems were
popular and influential before World War 1.
Symphony: a three- or four-movement orchestral
work, sometimes with choir, generally in sonata
form. Early sinfonias were single-movement
overtures; but by the middle of the 18th century, such
composers as Karl Stamitz were writing elaborate
symphonies in several movements. In the hands of
Haydn, Mozart. and Beethoven, the symphony
attained enormous depth, balance, and variety of
expression, ensuring that it remained a common form
for composers. The Romantic period both continued
the Classical tradition of the symphony-in the
works of Schubert, Mendelssohn, Schumann, and
Brahms - and initiated a new kind of symphony with
an implied or actual program, such as Beethoven's
Sixth Symphony and the symphonies of Berlioz,
Tchaikovsky, and Mahler. Twentieth-century
composers have continued to write symphonies, and
from Jean Sibelius and Carl Nielsen to Witold
Lutoslawski and Peter Maxwell Davies, they have
continually reconsidered and reinvented the form.
Syncopation: placing the strong beat on what are
normally the weaker beats in a bar. Thus, in a normal
four-beat bar, the accents would lie, in order of
strength, 1423. A syncopated bar would place the
strongest accent on the second or fourth beat, or even,
as in the rumba, on beats which lie between the
normal quarter-note beats.
Synthesizer: an electronic machine for producing
artificial sounds and tones with any desired
characteristic or quality, often recorded directly
onto magnetic tape for future performance through
System: a combination of two staves or more on
which all the notes to be played simultaneously in
different registers or on different instruments are
Tablature: a system of notation for plucked stringed
instruments, for instance lute or guitar, in which the
notes are indicated by means of the finger position
Tango: a slow ballroom dance of Argentine origin in
quadruple time, similar to the Cuban habanera.
Tarantella: an Italian folk dance in rapid 6/8 time,
characterized by light, quick hops and turns.
Temperament: tuning. Instruments may be tuned to
the exact pitches of a specific key, which would make
the intervals between different pairs of semitones not
precisely equal; or, as has generally been the case
since the 17th century, they may be tuned so that the
interval between B and C is the same as the interval
between C and C sharp, etc. This system, known as
equal temperament, is necessary if modulations from
the original key are to be possible.
Tenor: the highest natural male voice.
Tenuto: a marking that means "held," indicating that
the note should be sustained for its full value, and
even a little more.
Ternary form: a simple, common three-part form,
in the pattern ABA-that is, consisting of a first
section, then a second, contrasting section, followed
by a repetition of the first section.
Tessitura: the overall range of an instrumental or,
more commonly, a vocal part.
Theme: a melodic or, occasionally, harmonic idea
used as a fundamental unit in a musical form; also
Tie: a curved line indicating that two separate notes
should be played as a single note, the length of which
is the same as the sum of the length of the two
Timbre: the tone "color" of an instrument, voice, or
Time signature: the two numbers that indicate the
numbey of beats per bar of a piece of music, given at
the beginning of the first staff or system of staves,
and whenever the number of beats changes. The
lower number shows the length of note assigned one
beat (i.e., 2 as the lower number refers to half notes, 4
refers to quarter notes, 8 to eighth notes, etc.) and the
upper number shows how many of those notes are in
a single bar. Thus, 3/4 means three quarter notes to
the bar; 5/16 means five sixteenth notes. and so on.
Toccata: a fast keyboard piece, exploiting rapidity
of performance, runs, and repeated notes.
Tonality: the system of major and minor keys.
Tone: in American usage, a pitch; also the interval
of a major second.
Tone row: See Serial music.
Tonguing: in wind instruments, the articulation ol'a
note or group of notes by the silent sounding of the
consonant t or k.
Tonic: the fundamental note of a key; also, the triad
formed on that note.
Transcription: the rewriting of a piece of music
for instruments other than those for which it was
Transition: a bridging passage between sections in
Transposition: changing the pitch of a piece of
music up or down a given interval. so that the internal
relationships remain precisely the same.
Treble: the upper half of an entire vocal or
instrumental range, as opposed to bass; also, the
highest voice in choral singing.
Tremolo: the rapid repetition of a note, or the rapid
slurred alternation between two notes.
Triad: the basic form of three-note chord on which
all diatonic harmony is based; it consists of a tonic
plus the notes that lie a major (or minor) third and a
perfect fifth above it.
Trill: the quick repeated alternation between a note
and the note a semitone or whole tone above or
occasionally below it.
Trio: a work for three instruments; also, the middle,
contrasting section of a minuet or a scherzo.
Triplet: a group of three notes to be played in the
time normally taken by two.
Triple time: a time with three beats in the bar.
Tritone: the interval of the augmented fourth or
diminished fifth, equivalent to three whole tones.
Trope: an addition to or extension of the standard
Troppo: part of a tempo marking, meaning "too
much"; for example, Allegro ma non troppo means
"fast but not too fast."
Troubadours: court poet-musicians of southern
France, northern Spain, and northern Italy during
the Middle Ages, often of noble family themselves.
Tune: a melody.
Tuning: the raising or lowering of the pitch of
an instrument. or its strings, to produce correct
Turn: a formal ornamentation of the notes around
a principal note.
Tutti: a passage for the whole ensemble, or for the
orchestra without a soloist in a concerto.
Una corda: the muting (or damping) mechanism on
Unison: more than one instrument or voice playing
the same notes simultaneously.
Upbeat: the beat before a strong beat; also, the
conductor's signal immediately before the first entry.
Valves: on brass instruments, the pistons that alter
the pitch by changing the length of the tube through
which air passes.
Variation: a musical form consisting of a series of
progressively developed versions of a complete self-
contained theme, either an original one or, as is
common, a preexisting theme. Variation form is a
very widespread form in Classical slow movements.
as in Beethoven's Seventh Symphony.
Verismo: a style of Italian opera from the last
decade of the 19th century in which the setting is
contemporary to the composer's own time, the
manner is, to some extent, realistic, and the
characters are drawn from everyday life. Verismo
operas, of which the most famous is I Pagliacci
(1892) by Ruggiero Leoncavallo, are often
Vibrato: a rapid undulation in the pitch of a note, or
of two contiguous notes, made by an instrumentalist
or a singer to increase the expressiveness of a
Virtuoso: an instrumentalist or singer of great
Vivace: a tempo marking meaning "lively."
Vivo: a tempo marking meaning "with life."
Vocalise: a vocal style of singing without words, or
occasionally, a work for voice without words.
Voice: one of two or more parts in polyphonic
Voluntary: a piece for organ played before, during,
or after a church service.
Waltz: a dance in triple time of Austrian and
Bavarian origin, popular throughout Europe in the
19th century and afterwards, especially the Viennese
waltzes of Johann Strauss, Sr. and Jr. The waltz was
often incorporated into symphonic works in the place
of a scherzo, and independent concert waltzes
were written by such composers as Schubert, Chopin,
Brahms, Richard Strauss, and Ravel.
Whole note: a note equal in time value to two half
notes or four quarter notes; in Britain it is called
Whole-tone scale: a six-note mode that consists
only of whole-tone steps (for example, C, D, E, F
sharp, G sharp, A sharp), instead of the combination
of whole tones and semitones in other modes.
Word painting: in vocal music, a passage that
imitates some external element referred to in the
words at that point.
Yodeling: a folk-singing style switching from
falsetto to normal voice and back again; common in
Switzerland and the Tyrol.
Zarzuela: traditional Spanish comic opera, from the
17th to the 19th century, that has spoken dialogue
instead of recitative.