Sheet music, or music notation as it is known, employs a series of symbols and marks that pertain to certain notes, pitch, and tone. Music notations are visually represented symbols, which often include both modern and ancient musical symbols. Modern music notation which is commonly used by musicians of different genres throughout the world is said to have their origins in European classical music. This popular system uses a five-line staff to place the musical notes. Sheet music is used as a record or a guide to perform or compose a piece of music. To be able to read this sheet music, one has to study the musical notations, for which, one has to be acquainted with the symbols used to represent the notes. Given below is a list of the musical symbols employed to write sheet music. A double barline is used to separate two sections of music. A double bar line is also used to signify changes in key signature, time signature or major change in style and tempo. A dotted bar is used to sub-divide long measures of a complex meter into shorter segments. The stave, essentially, is mere lines; however, the presence of the clef marking the beginning of the stave is what assigns a certain pitch to the notes. The clef, in other words, helps to accurately relate to the pitch of the musical note placed on or between specific lines on the stave. In short, a clef is used to fix the position of certain high and low notes on the stave. Notes represent the length of time of a particular pitch. Each note stands for a particular number of beats. In written music, the length of a note is shown by its shape. When there is no note sounding, a rest is written, and the duration is shown by its shape. To make things easier, we have classified notes on the basis of their relation with the whole note or a semi breve. A hollow oval note head represents a whole note or a semibreve. The length of a full note is equivalent to four beats in a 4/4 time. A whole note receives 4 counts, which means, you have to hold the note for its full value. A whole rest corresponds to a whole note, which means, the rest period is equivalent to the duration of the musical note. A whole rest is denoted by a filled-in rectangle hanging under the second line from the top of the staff. Accidentals are notes that are used in musical notations to symbolize notes that fall between two main notes. The accidentals either raise or lower the note it precedes by a semitone. In other words, the notes placed before the corresponding note heads help raise or lower the pitch by half a tone. In written music, key signatures stand for a set of sharp of flat symbols placed on the stave. Key signatures are written adjacent to a clef placed at the beginning of a line of musical notation. The key signature is used to define the diatonic scale in a piece of music without the need of accidentals being employed for individual notes. A quarter tone music divides an octave into twenty-four equal intervals, that is better understood as twenty-four equal steps or tones. Quarter tone notation employs a new set of accidental signs or marks that add a microtonal value alongside a conventional sharp, flat, or natural note. Normal music has a regular pulse or throb which is termed as beats. These beats are grouped into regular groups to form the time or meter of the music. Time signatures are used to establish the number of beats in each uniformed section or measures. In a musical composition, notes are often grouped together to show the position of the beats in a bar. For a piece of work to be called music, the notes need to be synchronized and must fall smoothly in place. This harmony is brought about by the introduction of different note relationships or marks used to determine the relationship of one note with the other. Accents or articulations are used to specify how an individual note is to be performed within a musical passage. The articulation affects the transition or continuity on a single note or between multiple notes and sounds. Ornaments are embellishments or musical flourishes used to decorate a line in a musical piece. They are often used to modify the pitch pattern of individual notes in a single line of music. Marked by a mirrored letter 'S', lying on its side, the turn, or gruppetto as it is known, indicates a sequence of adjacent notes in the particular scale to be played. When placed directly above the note head, it implies that the auxiliary note be played before the principal note followed by the lower auxiliary note. Which means, you play a higher notes followed by the main note and play the immediate lower note and return to the principal note. When placed to the right of the note, you play the principal note before playing the turn sequence. In short, when the note is placed to the right you end up playing a quintuplet. Also known as the tremolando, it is symbolized by strokes through the stem of a note. Simply put, it indicates that a note be rapidly repeated to create a tremble or a shuddering effect depending on the instrument being used.