Bohr's orbit is nothing but a hypothetical path in which electrons move around the nucleus.
Bohr in his theory of the structure of an atom, describe these orbits as energy shells or energy levels in which electrons revolve around the nucleus in their fixed path.
These orbits resemble the orbits in the solar system except the electrostatic forces have attraction by these orbitals rather than gravity. However, the level of energy usually occupying an electron is called its ground state.
The energy of an electron in these stationary orbits remains constant and the electron can move from one orbit to another orbit only by emitting or absorbing the radiation energy in the whole of quanta.