What's Salat (prayer )-ul-Istikhara ?

Istikhara (Arabic) means to ask Allah to guide one to the right thing concerning any affair in one’s life, especially when one has to choose between two permissible alternatives, e.g. a career choice, getting married, etc. Similarly, a traveller should consult good righteous persons before setting out on a journey, because Allah says, “And consult them (O Prophet) in affairs (of moment),” (Qur’an