The Chakra System
The word chakra is Sanskrit (चक्र) for “wheel” and refers to energy centers that exist in the physical, emotional, and spiritual bodies. These force centers are points of connections at which energy flows from one body of a man to another. At each chakra, the concentrated energy spins around a central point, like a wheel spinning around an axle. Clairvoyants can see them in the etheric double. All these wheels are perpetually rotating and a force from the higher world is always flowing into them – in the undeveloped person usually sluggishly, while in a more evolved person they may be glowing and pulsating.
The seven main chakras are described as being aligned in an ascending column from the base of the spine to the top of the head. Each chakra is associated with a certain color, multiple specific functions, an aspect of consciousness, a classical element, and other distinguishing characteristics. Each of the chakras deals with a different aspect of human experience and produces a particular state of consciousness. The chakras also involve a hierarchy of needs, from physical and emotional to intellectual and spiritual. These energy centers have been correlated to colors, organs, and the Kabbalistic Tree of Life. The chakras are thought to vitalise the physical body and to be associated with interactions of both a physical and mental nature. They are considered loci of life energy, or prana (also called shakti, or chi), which is thought to flow among them along pathways called nadis.
Various traditions have different views about the number and exact location of the chakras. Some sources describe five or seven chakras, others eight. Some chakras are considered major, some minor, but most traditions refer to seven chakras that lie along the length of the spine, from the first chakra at its base to the seventh chakra about the crown of the head.
The chakras are described in the tantric texts the Sat-Cakra-Nirupana, and the Padaka-Pancaka, in which they are described as emanations of consciousness from Brahman, an energy emanating from the spiritual which gradually turns concrete, creating these distinct levels of chakras, and which eventually finds its rest in the Muladhara chakra.
The Eastern Chakra system
The Theosophist and author Kurt Leland writes about the Eastern system in his book Rainbow Body: A History of the Western Chakra System from Blavatsky to Brennan: 
The form of the Eastern system most familiar in the West appeared in The Secret Serpent, a 1919 publication by Sir John Woodroffe (1835-1936), a British judge on the high court of Calcutta. This book was an exposition of Tantra as it related to the chakras. The Eastern systems consisted of three primary nadis.
Mūlādhāra chakra (root support), also called guda (rectal) chakra.
Svādhiṣṭhāna chakra (own place), also called medhra (genital chakra).
Maṇipūra chakra, also called nābhî (navel) chakra.
Anāhata chakra (unstruck sound); also called hrdaya (heart) chakra. Certain types of yoga involve focusing on subtle sounds that become audible when one meditates on the heart center. Such sounds are considered to be modifications of a universal sound current set in motion by the absolute (Brahman) when the manifest universe was created.
Viśuddha chakra (purifying); also called kantha (throat) chakra.
Ājñā chakra (command); also called bhrūmadhya (brow) chakra. It is said that this is the chakra through which the commands of the guru come. Alternatively, it represents manas (mind) and its mastery indicates that the minds is under the practitioner’s command.
Talking about the ājñā chakra, Swami Satyananda Saraswati said:
There is a certain problem with the awakening of the other chakras. Each one contains a store of karmas or samskara, both good and bad, positive and negative, painful and pleasant. The awakening of any chakra will definitely bring to the surface an explosion or expression of these karmas, and of course, not everybody is prepared or ready to face them. Only those who have reason and understanding are able to cope. Therefore it is said that before you start awakening and manifesting the great force, it is best to purify the mind at the point of confluence. Then, with a purified mind, you can awaken the other chakras. 
He also said:
Ajna chakra is the point of confluence where the three main nadis or forces – ida, pingala and sushumna merge into one stream of consciousness and flow up to sahasrara, the crown center.
Sahasrāra chakra (thousand-fold); sometimes referred to by its location: mūrdhān (head/cranial vault). The usual English translation is “thousand-petaled lotus”. 
Location: Base of the body
Issues: Survival fear
Areas of Body: Eliminatory system, legs and feet
Balanced: Groundedness and safety
Excessively open: Extreme materialism, running to greed and hoarding
Blocked: Feeling insecure and disassociated from our body
Archetype: Earth Mother
Negative Archetype: Victim
Location: Four fingers below navel
Issues: Intimacy, emotions
Areas of Body: Reproductive organs and pelvic area
Balanced: Healthy sexuality and emotions; enthusiasm
Excessively open: Weak boundaries
Blocked: Tendency to be very rigid
Archetype: (Physical) love
Negative Archetype: Martyr, denying his/her own pleasure
Location: Solar plexus
Issues: Self-esteem, ego, feelings of autonomy
Areas of Body: Stomach, liver, small intestine
Balanced: Healthy social roles
Excessively open: Aggression in a bullying way
Blocked: Selfless behavior motivated by personal worthlessness
Negative Archetype: Servant or slave
Issues: Compassion, optimism/pessimism
Areas of Body: Heart, lungs, shoulders, arm
Balanced: Unconditional love
Excessively open: Co-dependent love
Blocked: Withdrawal from love, fear of being wounded
Negative Archetype: Actor
Issues: Communication, intuition
Areas of Body: Throat, mouth
Balanced: Inner directed Self
Excessively open: Using speech as mechanism of control
Blocked: Unable to communicate about important issues
Archetype: Communicator, artist
Negative Archetype: Silent child
Location: Third eye
Issues: Dedication to spiritual path; clarity and insight
Areas of Body: The senses
Balanced: Calm and focused
Excessively open: Delusion
Blocked: Denial what is seen
Archetype: Seer, visionary
Negative Archetype: Intellectual
Location: Crown of head
Color: Crystal light
Issues: Spiritual separation
Areas of Body: Brain and nervous system
Balanced: Unity consciousness
Excessively open: Spiritual addiction
Blocked: Limited in our ability to believe or have faith
Archetype: Guru (within), sage
Negative Archetype: Egotist (belief of being separate from others)
. Charles Webster Leadbeater, Annotations by Kurt Leland, The Chakras, (Wheaton, Ill: The Theosophical Publishing House, 2013), p. 1- 5 . The Kabbalah, Thelemapedia: The Encyclopedia of Thelema, accessed April 2020. . The Chakra, Theosophy Wiki. accessed April 2020. . Kurt Leland, Rainbow Body: A History of the Western Chakra System from Blavatksy to Brennan, (Lake Worth, Fl: Ibis Press, 2016), 47-51. . Swami Satyananda Saraswati, Kundalini Tantra (Munger, Bihar, India: Yoga Publications Trust, 2001), Chapter 3.