When learning to play the the harp, in addition to the many musical terms and symbols which are common to all instrument, there are also many terms and symbols which are specific to the harp. I've compiled a list of these here, showing an example from musical notation and an explanation of the term or symbol.
Finger numbers
These numbers correspond to individual fingers and are the same as the system used on the piano. 1 = thumb, 2 = index finger, 3 = middle finger, 4 = ring finger. There is no 5 as the little finger is not used in playing the harp.
A bracket shows fingers that are placed together. Preparing the fingers before you play is a crucial aspect to harp play. Any fingers shown within the bracket rest directly on the strings, while each finger is played individually. Each finger maintains direct contact with the string until it has been played.
Overlapping Brackets (sometimes shown as dashed lines)
This is an extension of placing, and is sometimes called placing in two directions (up and down, or down and up). The initial bracket shows fingers that are placed on the strings before beginning to play, and just before you reach the last finger in the bracket, a new group is added on. From the start to the end of overlapping brackets, at least one finger is always maintaining contact with the strings.
Check Mark or Breath Mark, sometimes a dot
This is the opposite of placing. It simply means to come away from the strings, to release all contact with the strings for a moment, before returning to them.
R. H. and L. H
Just as with piano music, harpists use R. H. and L. H. as an abbreviation for Right Hand and Left Hand as a designation for which hand should be playing.
Lex deux mains, M. D. and M. G.
Harpists tend to play a lot of French repertoire, which frequently includes French markings. Les deux mains translates to both hands. M. D. is an abbreviations for Main Droite, meaning right hand, and M. G. is an abbreviation for Main Gauche, meaning left hand.
M. D. and M. S
Sometimes you see these same markings in Italian. M. D is an abbreviation for Mano Destra, meaning right hand. M. S. is an abbreviation for Mano Sinistra, meaning left hand.
Thumb Slide
This means to play the thumb twice in a row, but without coming away. The thumb simply slides from one string to the next. This is especially useful for descending five finger passages.
Fourth Finger Slide
This is quite similar to a thumb slide, only the fourth finger is used instead, sliding directly from one string to the next. Useful for ascending five finger passages.
A muffle means to dampen the strings, to stop the vibrations and silence the sound. Since the harp is an instrument of resonance, this is an important part of playing the harp.
Below the staff - middle of staf?
Muffle a specific range of strings
This type of muffle shows that only a specific range of strings should be dampened, only the strings that fall within the top and bottom diamond.
Muffle a specific string
Here only one string should be muffled, shown with a diamond note head.
L. V.
This is a common marking in harp music. It's an abbreviation for the French Laissez Vibrer, meaning to let vibrate. Rather than muffling the strings, you let them ring.
Flat Thumb (in addition to the symbol, sometimes Étouffée, the French name is written.)
This is technique of playing that involves playing each note with a thumb while laying the palm and fingers of the hand flat on the strings. It's done with the left hand only, and can give a bit more distinct sound, as a muffle is naturally built in to the technique.
Knuckle Muffle
In this technique, generally only played by the right hand, notes are played with the index finger in an ascending scale and as the harpist prepares each subsequent note, the knuckle is used to muffle the previously played string.
Chords​
Rolled Chords (or arp.)
A classic harp technique! This means to arpeggiate the chord, playing the notes quickly in succession, rather than all simultaneously. The default is to roll all chords upwards, starting with the lowest note and ending with the highest note.
Rolled Chord with a Downwards Arrow
Although not common, sometimes you roll a chord starting with the highest note and ending with the lowest note. This symbol shows this alternate arpeggiating technique.
Rolled Chord with an Upwards Arrow
This means to roll upwards, starting with the lowest note and ending with the highest note. It's a redundant notation, as you play this exactly the same as the first example in this section. Consequently, this symbol is generally only found in music where the downward arrow is used, as a courtesy to avoid confusion.
Chord with Arpeggiated Grace Notes
This is simply another, really unambiguous way, of showing that the chord must be rolled or arpeggiated. It's not very common, but comes up from time to time.
Chord with a Vertical Bracket (or non. arp)
This is the opposite of a rolled chord, to play the chord as a block, all notes simultaneous.
Glissandos
Glisses
Glisses or glissandos are frequently found in harp music. Here this gliss (correctly) shows the starting and ending pitches as well as the seven notes contained within the gliss so that the harpist can set their levers or pedals appropriately.
Continuous Glisses
Here the glisses continue changing direction when shown. Harpists can either play this using one or two hands, depending on personal preference. Again the starting, and ending pitches are shown, as well as the seven notes contained within the gliss.
Non specific glisses?
Multiple Glisses
These glisses are meant to be multiple glisses in the same direction. This can be done with one hand or split up between the hands at the harpist's discretion.
Gushing Chords or Aeolian Chords?
This is a type of gliss, generally played a bit more rhythmically than a typical gliss. The arrow designates the direction of the gliss (upwards or downwards) and the range of the gliss is shown by the outer notes.
Aeolian Chords?
Standard Techniques
PDLT (wavy line)
PDLT is an abbreviation for Près de la table, meaning to play on the sound board in French. The harpist does exactly that in this technique, sliding their fingers lower on the strings vertically until they are quite close to the sound board. The resulting sound is a bit more nasal and less resonate than the usual sound. This is an extremely common harp technique.
If PDLT is written with a symbol, then it functions like an 8va symbol, lasting until the dashed line ends. If the text "PDLT" is written then it functions like a dynamic marking, lasting until canceled. Generally ordinaire, normale, or position normale are written to show that the harpist should return to the normal playing position.
BDLC is a variation of PDLT. It's an abbreviation for Bas dans les cordes, meaning lower on the strings in French. The playing position for this is not as extreme as PDLT, and the resulting sound is not as nasal as a true PDLT. It is less commonly seen than PDLT.
Single Harmonic
A harmonic is a common effect on the harp, played by dampening the bottom half of the string while plucking the top half. Generally speaking, harmonics are written where they are played and will sound an octave higher. This is considered standard notation.
Some composers do the opposite and wrote harmonics where they sounded, so the harpist must play these an octave below. Carlos Salzedo is a notable example - harmonics in all of his music are written where they sound. Other composers sometimes include a footnote explaining which method is being used for harmonics.
Multiple Harmonics
The number of circles shown equals the number of harmonics played.
Bisbigliando
This literally means "to whisper" in Italian. It's played using the same technique as a two- handed trill, although it frequently involves more than two strings. Sometimes enharmonics are used to enhance the soun
Tapping on the soundboard comes up fairly often in harp music. A diamond shaped note head is most common, although sometimes composers use other alternate note heads. Generally the harpist will tap on the soundboard, although you can also tap on the body of the harp. It's possible to tap with finger tips or the palm of the hand, or use the knuckles for a knocking sound. Sometimes the composer specifies one of these forms of tapping and other times it's left up to the discretion of the performer.
Extended Techniques​
The xylo effect requires two hands, one hand to muffle the strings at the point where they connect with the soundboard, and the other hand to play the strings. It creates a sound quite similar to a xylophone.
Thunder is an effect works best using the base wires and the left hand. The performer strikes the strings with the flat of their hand, creating an indistinct mass of sound. It can be quite loud.
Nail Effect
Here the performer uses the tip of their nail to play the string, creating a metallic sound. It can be a little bit difficult to do, as you have to make sure your nails are long enough to be able to use them to use, but not too long to get in the way of regular playing. It also is difficult to do quickly, as time is required to get the nail into position. It creates a distinctive, but not very loud sound.
Nail Glisses
These are simply glisses uses the nails, quite easy to do, and fun to play. Generally the performer flips the traditional gliss fingering, and descending glisses are with the back of the 2nd finger, and ascending glisses are with the back of the thumb. (Note: I couldn't decide whether to put this in the gliss section or here in the extended technique section. They're certainly more common than the regular nail effect.)
Thunder Gliss
This has nothing to do with the earlier thunder technique, but is instead simply a form of gliss. These are played on the low wire strings, generally only with the left hand. The gliss is purposely overplayed so that the strings rattle and strike each other while resonating. This is definitely one of the loudest possible extended techniques.
Son Pincés
In this extended technique, the performer takes the string between the thumb and index finger and plucks quite hard, giving it a pinch. This creates a percussive sound. The only composer I personally have seen use this technique is Bernard Andrès.
Here the performer simply slides the palm and fingers of their hand up and down the wire strings, creating a soft whistling sound.
The performer plays a string with their right hand, and then immediately using their left hand to press the string rapidly just below the bridge pin, using an in and out motion. This only works well on the higher strings, particularly strings made out of nylon rather than gut.
Lever Slides
First play the string in question with the right hand, then quickly move the lever with the left hand, so that the half step change is audible. This is frequently used for a jazzy effect.
Pedal Slides
Rather than smoothly and quietly moving the pedal from one notch to another, the goal here is hear the sound of the string changing by a half step. First play the string, then move the pedal while it is still resonating. This works best with the low strings.
Pedal Buzz
This is a purposeful misuse of the pedal. Hold the pedal half way between two notches and then play a low wire string. The result is an ugly, clanging noise, one of the loudest extended techniques available.