The names of the patterns, and the associated number of movements (including the diagrammatic symbol of each pattern) symbolizes either heroic figures in Korean history, or instances relating to historic events.
Originally, there were 24 patterns in Tae Kwon Do. This reason for this was explained by General Choi (founder of the present day Taekwon-Do) as:
Additional patterns have been added by Grand Master Park Jung Tae to further enhance the basic set of 24. Grand Master Park’s theory is essentially there are not enough hours in one day to fully appreciate Taekwon-Do – as such additional hours in each day would be required to truly become enlightened. Grand Master Park’s additional patterns compliment the basic set, and provide a mechanism for additional training.

Grand Master Park Jung Tae was the senior Technical advisor to the I.T.F. He was regarded as the World’s number one authority on the technicalities of Taekwon-Do, which is demonstrated when examining the new patterns that he has created.

Note
All patterns are taught using the key that is displayed on the pattern diagrams (the letters at each of the points). A pattern is started on the spot marked with an ‘X’ facing towards ‘D’ with ‘A’ always on your right hand side.
(c) 2009 itkdc.com
• The pattern should begin and end in exactly the same spot. This will indicate the performer's accuracy.

• Correct posture and facing must be maintained at all times.

• Muscles of the body should be either tensed or relaxed at the proper critical moments in the exercise.

• The exercise should be performed in a rhythmic movement, with an absence of stiffness.

• Movements should be accelerated or decelerated accordingly.

• Each pattern should be perfected before moving on to the next.

• Students should know the purpose of each movement.

• Students should perform each movement with realism.

• Attack and defense techniques should be equally distributed amongst right and left hands and feet.
Before describing each of the patterns in detail, the following extracts and quotations lay down the underlying philosophy (and basic principles) of patterns in Taekwon-Do.

The ancient law in the Orient was similar to the law of Humarabi, an eye for an eye, a tooth for a tooth, and was rigorously enforced even if death was caused accidentally. In this type of environment, and since the present system of free sparring had not yet been developed, it was impossible for a student of the martial arts to practice or test his individual skill of attack and defence against actual moving opponents. Individual advancement was certainly hindered until an imaginative practitioner created the first patterns.

Patterns are various fundamental movements, most of which represent either attack or defense techniques, set to a fixed and logical sequence.

The student systematically deals with several imaginary opponents under various assumptions using every available attacking and blocking tools from difference directions. Thus pattern practice enables the student to go through many fundamental movements in series, to develop sparring technique, improve flexibility of movements, master body shifting, build muscles and breath control, develop fluid and smooth motions, and gain rhythmical movements.

It also enables a student to acquire certain special techniques, which cannot be obtained from either fundamental exercises, or from sparring. Accordingly, patterns, being the ledger of every movement, are a series of sparring, power test, feats and characteristic beauty.

Though sparring may merely indicate that an opponent is more or less advanced, patterns are a more critical barometer in evaluating an individual’s technique.

The following points should be considered while performing patterns: