Human life falls under two grand divisions- fortunes and misfortunes. Fortunes are related to health, personality, success in politics, financial gains, educational benefits, mental strengths etc and misfortunes are related with sorrows, sources of sorrows, worries, miseries, troubles, physical and mental deformities, bad children etc.

The complete horoscope is divided into 12 houses. Out of these 12 houses 6 are considered to be favourable and 6 as unfavourable. House number 6, 8 and 12 are considered as the most unfavourable houses of all the  houses and are grouped together as Trik Houses.

Sixth House

The sixth house represent disease, wounds, debts, sorrows, accidents, mental imbalances, misfortunes related to children and brothers. To understand the horoscopic effect of 6th house we need to study the position of 6th house lord, planet in the 6th house, Aspect on the 6th house, planets associated with the 6th lord. Mars is considered to be most beneficial for 6th house.. Every rashi is related to some or the other parts of body or internal organs. The rashi in the 6th house specifies the most affected body part. for example if in the 6th house it is Libra then skin will be most affected as Libra represents skin. Also, every planet represents one or the other body part hence the planet placed in the 6th house will affect that part. for example, if Jupiter is placed in the 6th house then Lever and other parts related to Jupiter will be affected.

Eighth House

8th house is the other Trik house. It represents longevity, legacies, nature of death, disgrace, degradation and details pertaining to death.  To understand the horoscopic effect of the 8th house we need to study the position of the 8th lord. the planet placed in the 8th house, Aspect on the 8th house, planets associated with the 8th house. Placement of malefics in the 8th house lead to unnatural death of the native such as suicide, accident, murder. if more benefics influence the 8th house then the death will be natural that is either old age or disease. If 6th and 8th houses are related then death will be after ill health. 8th house also depicts the Early death, Short life.

Twelfth House

12th house is the 3rd trik house representing losses, extravagance, expenditure, confiscation etc. The factors to be considered in analyzing this house are the lord of 12th house, planets placed in the 12th house,  planets aspect the 12th house, association of 12th house lord with other planets. If 12th lord in any bhava or house subject to malefic aspect or association will cause debt, expenses, involvement in unhealthy wicked company during its dashas and bhuktis.

These trik houses are individually  most efficient to produce evil results and situations in natives life.  But if they  interchange their positions i.e if lord of 6th is placed in the 8th or lord of 8th placed in the 6th or lord of 6th placed in the 12th or vice-versa , they produce good results.