Nepotism is the granting of jobs to one's relatives or friends in various fields, including business, politics, entertainment, sports, religion and other activities. Nepotism is the act of using one's power to get good jobs or unfair advantages for the members of your family when the members of your family do not deserve it. The term originated with the assignment of nephews to important positions by Catholic popes and bishops. Trading parliamentary employment for favors is a modern-day example of nepotism.
Nepotism refers to partiality to family whereas cronyism refers to partiality to a partner or friend. Favoritism, the broadest of the terms, refers to partiality based upon being part of a favored group, rather than job performance. Favoritism is a part of any human society and the two branches of favoritism are cronyism and nepotism. Situations of nepotism refer to when a politician’s son gets a similar political position in a country, and situations when relatives of high ranking officers get easy positions in their career. This happens despite the relatives lacking the necessary qualifications. Situations of cronyism refer to where someone might get a position in a company since he is a friend of the company CEO. Nepotism and cronyism have negative consequences because the truly qualified and talented people have to face injustices and it eventually leads to corruption and brain drains. Moreover, these three are unethical practices that create social discrimination. 
Origin of the modern concept and etymology
Borrowed from the French term 'Nepotisme', which in turn was derived from Italian 'Nepotismo' and the Latin 'nepōs' (nephews), nepotism refers to the practice of popes appointing relatives during the Middle Age and Renaissance. The term comes from the Italian word nepotismo, which is based on the Latin word nepos (nephew).
Several popes elevated nephews and other relatives to the cardinalate. Often, such appointments were a means of continuing a papal "dynasty". For instance, Pope Callixtus III, head of the Borgia family, made two of his nephews cardinals; one of them, Rodrigo, later used his position as a cardinal as a stepping stone to the papacy, becoming Pope Alexander VI. Alexander then elevated Alessandro Farnese, his mistress's brother, to cardinal; Farnese would later go on to become Pope Paul III.
Paul III also engaged in nepotism, appointing, for instance, two nephews, aged 14 and 16, as cardinals, as well as making efforts to increase the territories of his illegitimate son Pier Luigi Farnese. The practice was finally limited when Pope Innocent XII issued the bull Romanum decet Pontificem, in 1692. The papal bull prohibited popes in all times from bestowing estates, offices, or revenues on any relative, with the exception that one qualified relative (at most) could be made a cardinal.
In ancient literature
In the second book of the Kural literature, which forms a manual for governments and corporations, Valluvar suggests about nepotism and favouritism thus: "If you choose an unfit person for your job just because you love and you like him, he will lead you to endless follies."
It is a common accusation in politics when the relative of a powerful figure ascends to similar power seemingly without appropriate qualifications.
The British English expression "Bob's your uncle" is thought to have originated when Robert Arthur Talbot Gascoyne-Cecil, 3rd Marquess of Salisbury, promoted his nephew, Arthur Balfour, to the esteemed post of Chief Secretary for Ireland, which was widely seen as an act of nepotism.
One other recent example is the current Portuguese government which counts no less than 50 nominations within family ties. Another more recent example can be found in the political activity in South Carolina, particularly in relation to Governor McMaster, who initially gained his position after becoming the first high level state official to endorse current President Donald Trump and subsequently rose from lieutenant governor to governor of the state when President Trump appointed Nikki Haley to be the United States ambassador to the United Nations. Governor McMaster then went on to attempt to force a vote for the President of the University of South Carolina ahead of schedule, and in favor of his favorite candidate, Robert Caslen Jr., former superintendent of West Point Academy who was favored by President Trump and previously interviewed by the Trump administration for the position of National Security Advisor.
Nepotism can also occur within organizations when a person is employed due to familial ties.
It is generally seen as unethical, both on the part of the employer and employee.
Nepotism at work can mean increased opportunity at a job, attaining the job or being paid more than other similarly situated people. Arguments are made both for and against employment granted due to a family connection, which is most common in small, family run businesses.
On one hand, nepotism can provide stability and continuity.
Critics cite studies that demonstrate decreased morale and commitment from non-related employees, and a generally negative attitude towards superior positions filled through nepotism.
An article from Forbes magazine stated "there is no ladder to climb when the top rung is reserved for people with a certain name." Some businesses forbid nepotism as an ethical matter, considering it too troublesome and disruptive. According to an article published in Journal of Economic impact  "Financially strong families can easily influence on the hiring process for obtaining a job.
Outside of national politics, accusations of nepotism are made in instances of prima facie
Peaches Geldof's role as magazine editor in an MTV reality show—produced by a company owned by her father, Bob Geldof.
Hollywood's Coppola family includes many distinguished filmmakers and actors. The careers of Sofia Coppola, Nicolas Cage, and Jason Schwartzman have been attributed to aid by director Francis Ford Coppola, who cast his daughter Sofia in The Godfather Part III. Cage changed his last name in order to distance himself from claims of nepotism.
Kevin Feterik was installed as the starting quarterback of the Calgary Stampeders in 2003 at the insistence of his father Michael, who bought the team in 2001.
In the popular chat show ‘Koffee with Karan’, Kangana Ranaut called the famous film - maker Karan Johar, the ‘flag – bearer of nepotism’.
List of cardinal-nephews