Lingas of Śiva -Linga means outer form. Outer body form indicates sex of the person, so it means sex also.

मूल स्वरूप लिङ्गत्वान्मूलमन्त्र इति स्मृतः । सूक्ष्मत्वात्कारणत्वाच्च लयनाद् गमनादपि । लक्षणात्परमेशस्य लिङ्गमितयभिधीयते ॥ (योगशिखोपनिषद्, २/९, १०)

Linga = Līnam + gamayati = i.e. it goes to merge in. The root cause gives rise to world which again merges in it, that micro form is called mūla-mantra (svayambhū-linga). Next is gamana (motion) called bāņa-linga. Bāņa means arrow which is used to indicate direction of motion.

Signs of Parameśvara (its created objects in which it has entered) are also linga. These are itara (=other, different) forms, so they are called Itara-linga. In space, root world as uniform rasa is Svayambhū linga.

Motion pattern starts with galaxy, which is bāņa -linga.

   Various forms are seen on earth and solar system, they are infinite, but classified as 12 rāśi (zodiac signs). In those, jyoti (light) of sun varies, so they are called jyotirlinga. On earth, centre of civilization is India which is place of norms of conduct. So, all lingas are here only.

At the end of Jagannātha dhāma, Lingarāja is at Bhubaneshwar, Orissa. Adjacent to it, Trilinga is in Telangana in Andhra-pradesh. 12 jyotirlingas are in whole of India.

   In human body, the linga in mūlādhāra at center of orifices of stool and urine is the organ from where man is born, so it is svayambhū linga. Center of blood and air circulation is at heart chakra-anāhata- which is place of bāņa-linga. Forms are perceived by centre of brain whose linga is called Itara-

योनिस्थं तत्परं तेजः स्वयम्भू लिङ्ग संस्थितम् । परिस्फुरद् वादि सान्तं चतुर्वर्णं चतुर्दलम् ।

कुलाभिधं सुवर्णाभं स्वयम्भू लिङ्ग संगतम् । हृदयस्थे अनाहतं नाम चतुर्थं पद्मजं भवेत् ।

पद्मस्थं तत्परं तेजो बाण लिङ्गं प्रकीर्त्तितम् । आज्ञापद्मं भ्रुवो र्मध्ये हक्षोपेतं द्विपत्रकम् ।

तुरीयं तृतीय लिङ्गं तदाहं मुक्तिदायकः । (शिवसंहिता, पटल ५)

Comparison of lingas-

Linga                Cosmic      Geographical        Human

Svayambhū   Root world     Lingarāja          Mūlādhāra

Bāņa            Galaxy          Trilinga             Anāhata

Itara          Solar system    12 jyotir lingas     Ājñā

Turīya     Abstract World        ---------          Sahasrāra

Representation of forms is by symbols of letters forming words and sentences-that also is called Linga and is described in Linga purāņa (1/17/83-88) which tells about number of letters for different purposes. Thus in Greek also, it is called Lingua and language in English-

शुद्ध स्फटिक संकाशं शुभाष्टस्त्रिंशदाक्षरम् । मेधाकरमभूद् भूयः सर्वधर्मार्थ साधकम् ॥८३॥

गायत्री प्रभवं मन्त्रं हरितं वश्यकारकम् । चतुर्विंशति वर्णाढ्यं चतुष्कलमनुत्तमम् ॥८४॥

अथर्वमसितं मन्त्रं कलाष्टक समायुतम् । अभिचारिकमत्यर्थं त्रयस्त्रिंशच्छुभाक्षरम्॥८५॥

यजुर्वेद समायुक्तम् पञ्चत्रिंशच्छुभाक्षरम् । कलाष्टक समायुक्तम् सुश्वेतं शान्तिकं तथा॥८६॥

त्रयोदश कलायुक्तम् बालाद्यैः सह लोहितम् । सामोद्भवं जगत्याद्यं बृद्धिसंहार कारकम् ॥८७॥

वर्णाः षडधिकाः षष्टिरस्य मन्त्रवरस्य तु । पञ्च मन्त्रास्तथा लब्ध्वा जजाप भगवान् हरिः ॥८८॥

(लिङ्ग पुराण १/१७)

38 letters-for intellect, wealth (37 letters of Maya script + Om)

24 letters of Gāyatrī-For influence, fame.

33 letters (Kŗşņa Atharva)-For Abhichāra (curse, destruction etc)

35 letters of Yajurveda (Gurumukhī)-Yajña (cycle of production), peace.