What is behind Lord Shiva being represented as a 'Linga?'

What is behind Lord Shiva being represented as
a 'Linga?' The popular belief is that the Shiva
Linga or Lingam represents the phallus, the
emblem of the generative power in nature.
According to Swami Sivananda, this is not only a
serious mistake, but also a grave blunder.
Shiva Linga: The Symbol for Shiva
In Sanskrit, Linga means a 'mark' or a symbol,
which points to an inference. Thus the Shiva
Linga is a symbol of Lord Shiva - a mark that
reminds of the Omnipotent Lord, which is
formless.
Shiva Linga speaks to the devotee in the
unmistakable language of silence, and it is only
the outward symbol of the formless being, Lord
Shiva, who is the undying soul seated in the
chambers of your heart, who is your in-dweller,
your innermost self or 'Atman,' and who is
identical with the supreme 'Brahman.'
The Linga as a Symbol of Creation
The ancient scripture Linga Purana says that the
foremost Linga is devoid of smell, colour, taste,
etc., and is spoken of as 'Prakriti' or Nature
itself. In the post-Vedic period, the Linga
became symbolical of the generative power of
Lord Shiva.
The Linga is like an egg, and represents the
'Brahmanda' or the cosmic egg. Linga signifies
that the creation is effected by the union of
'Prakriti' and 'Purusha,' the male and the female
powers of Nature. Linga also signifies 'Satya,'
'Jnana' and 'Ananta' - Truth, knowledge and
Infinity.
The 3 Parts of a Shiva Linga
A Shiva Linga consists of three parts, the lowest
of which is called the 'Brahma-Pitha,' the
middle one, the 'Vishnu-Pitha' and the
uppermost one, the 'Shiva-Pitha.'
The Holiest Shiva Lingas of India
There are 12 'Jyotir-lingas' and 5 'Pancha-bhuta
Lingas' in India. The dozen Jyotir-lingas are:
Kedarnath, Kashi Vishwanath, Somnath, Baijnath,
Rameswar, Ghrusneswar, Bhimshankar, Mahakal,
Mallikarjun, Amaleshwar, Nageshwar and
Tryambakeshwar. The 5 Pancha-bhuta Lingas
are: Kalahastishwar, Jambukeshwar,
Arunachaleshwar, Ekambareshwar of Kanjivaram
and Nataraja of Chidambaram. The temple of
Lord Mahalinga at Tiruvidaimarudur known also
as Madhyarjuna is regarded as the great Shiva
temple of South India.
The Quartz Shiva Linga
The 'Sphatika-linga' is made up of quartz. It is
prescribed for the deepest kind of worship of
Lord Shiva. It has no color of its own, but takes
on the color of the substance which comes in
contact with it. It represents the 'Nirguna
Brahman' or the attribute-less Supreme Self or
the formless Shiva.
What the Linga Means to Devotees
There is a mysterious or indescribable power or
'Shakti' in the Linga, to induce concentration of
the mind, and helps focus one's attention. That
is why the ancient sages and seers of India
prescribed Linga to be installed in the temples of
Lord Shiva.
For a sincere devotee, the Linga is not merely a
block of stone. It is all-radiant - talks to him,
raises him above body-consciousness, and helps
to communicate with the Lord. Lord Rama
worshiped the Shiva Linga at Rameshwaram.
Ravana, the learned scholar, worshiped the
golden Linga for its mystical powers