<center>DEADLOCK PREVENTION</center>
This ensure that at least one of this conditions can not cope by preventing occurrence of a deadlock.

<center>There are four ways to prevent deadlock</center> 
* MUTUAL EXCLUSION
Not require for shareable resources must hold for non-shareable resources.
* COLD MUD
This must guarantee that when ever a process requests a resources, it does not hold any other resources.
* NO PREMPTION
If a process that is holding some resources request another resources, that can not be immediately allocated to it, then all the resources currently being hold are released.
* CIRCULAR WAIT
Impose in total ordering of all resources types and require that each process request resources in an increasing order of enumeration.
<center>https://steemitimages.com/DQmSvQ4hwrbMLLa3wPBYFcmwAJiVzb5BFPYDCyLZzExmUaB/image.png</center>
<center>Image credit: [Wikimedia Commons](https://upload.wikimedia.org/wikipedia/commons/thumb/7/71/Dekker%27s_Algorithm.svg/2000px-Dekker%27s_Algorithm.svg.png), public domain</center>

<center>DEADLOCK AVOIDANCE</center>
* Simplest and the most useful model requires that each process declare the maximum number of resources of each type that it may need.
* The deadlock avoidance algorithm dynamically ex-ermines the result allocation state to the ensure that there can never be a circular wait condition. Resources allocation state as defined by the number of available and allocated resources and the maximum demands of the processes.
<center>https://steemitimages.com/DQmYpW9KzsCPRCfWusHHoVv2EjjwFgDn2e7rCBTBdyd99gC/image.png</center>
<center>Image credit: [Wikimedia Commons](https://upload.wikimedia.org/wikipedia/commons/thumb/3/37/CSMACD-Algorithm.svg/2000px-CSMACD-Algorithm.svg.png), public domain</center>

<center>DEADLOCK DETECTION</center>
If the system doesn't employ a deadlock prevention or a deadlock avoidance. An algorithm then a deadlock situation may occur. In those environment the system must be able to provide.
* An algorithm that ex-ermine the state of a system to determine if a deadlock has occurred.
* An algorithm to recover from a deadlock.
<center>https://steemitimages.com/DQmV3wL9V6EW3TuupzxKUtKZo8EM772idgpexNQXkfCJMnM/image.png</center>
<center>Image credit: [Wikimedia Commons](https://upload.wikimedia.org/wikipedia/en/5/50/RoundRobin.jpg), public domain</center>