Yoga originated in ancient India centuries ago.  It means "union" in Sanskrit.  At its core is the practice of meditation to balance mind, body and spirit.  Yoga works on the concept that illness and diseases happen if our energy flow throughout the body are blocked or hampered.  By meditation, yoga releases the obstruction and let the proper energy flow through once more. Yoga doesn’t fall behind other alternative medicines since it can cure health conditions like asthma, bronchitis, high blood pressure, back pain, diabetes, and arthritis to name a few.  It also promotes anti-ageing, weight reduction and also treats insomnia.

Yoga is made up of different postures or asanas.  It involves gentle stretches, breathing practices, and gradual deep relaxation. A beginner should go slowly and shouldn’t overexert the body.  There are classic postures which are being used in yoga.  One of these is the sit/easy position or Sukhasana. This is yoga’s starting position.  It strengthens the lower back and opens the hips and groins.  Next is Mountain or Tadasana which develops balance, posture and self-awareness. 
Here are various yoga postures:

The Bridge or Sethu Bandhasa. 
Promotes flexibility and suppleness while strengthening the lower back and abdominal muscles. 

The Forward Bend or Extension also called Uttanasana   
Improves the elasticity of the legs and spine, and gives the heart and neck respite.

The Triangle or Trikonasana
Improves elasticity of the spine and helps develop balance and concentration. Another is the dog and cat position which focuses on spine flexibility. 

The cobra or Bhujangasana.  
Improves elasticity of the spine and strengthens the arms and the back. An alternative position is the downward facing Dog also known as Adho Mukha Svanasana. This position develops strength, flexibility and awareness.  It also gives respite to the heart. 

The Half Shoulder or Ardha Sarvangasana
Strengthens the  abdomen, improves blood circulation and promotes thyroid function.

The Corpse or  Savasana 
Refreshes, relaxes and quiets the body and mind.

The Head to Knee or Janu Shirshasana
Stretches back and hamstring while improving flexibility.

The Warrior II or Virabhadrasana II
Toughens legs and arms and also improves concentration and balance. 

All postures, with proper breathing and meditation, are there to let you find your equilibrium.  Promising a healthy balance of mind and body, Yoga helps restore the energy flow you had as a healthy person and maintain it that way.  More than an alternative cure, yoga is basically a way of life – a healthy and active life.