A prison escape (referred as a bust out, breakout, jailbreak, or prison break) is the act of an inmate leaving prison through unofficial or illegal ways. Normally, when this occurs, an effort is made on the part of authorities to recapture them and return them to their original detainers. Escaping from prison is also a criminal offense in some countries, such as the United States and Canada, and it is highly likely to result in time being added to the inmate's sentence, as well as the inmate being placed under increased security that is most likely a maximum security prison or supermax prison. In Germany, and a number of other countries, it is considered human nature to want to escape from a prison and it is considered as a violation of the right of freedom, so escape is not penalized in itself (in the absence of other factors such as threats of violence, actual violence, or property damage). Many prisons use security features such as CCTV, perimeter sensors, barred windows, high walls, barbed wire, razor wire, and electric fencing to prevent escapes. Methods Numerous methods have been used to escape from prisons over time. Many escapes have been successfully conducted by inmates who have invented their own methods. Weaknesses that are found as prisoners escape are often corrected at numerous prisons around the world to prevent future escapes in a similar manner. This leads inmates to finding new ways. Since prisoners usually have a lot of time in which they are doing nothing, this gives them plenty of time to think, allowing them to devise plans and figure out ways to escape. The following are methods that have commonly been used by prisoners in escapes. In some instances, a combination of these are used. Cell escape While some prisoners are allowed out of their cells at times, others remain locked in their cells most of the time, particularly those in solitary confinement. Many prisoners who are kept in their cells must find ways out of the cells. Even those who are allowed out of their cells at times still have plans that involve escape from their cells. Cell escapes occur through either the door, the window, the light, the ventilation system, by breaking down the walls, or by tunneling underground. Some prisoners have escaped by picking the locks on their cells, creating keys to their cells, sawing bars off of