Piled Higher and Deeper

Piled Higher and Deeper (also known as PhD Comics), is a newspaper and webcomic strip written and drawn by Jorge Cham that follows the lives of several grad students. First published in 1997 when Cham was a grad student himself at Stanford University, the strip deals with issues of life in graduate school, including the difficulties of scientific research, the perils of procrastination, and the complex student–supervisor relationship. As of 2017, the strip's website received 6 million visitors each year.
History.
"Piled Higher and Deeper" was first published in The Stanford Daily, the student newspaper at Stanford University, in October 1997. The newspaper had put out a call for comics and Cham, a student and teaching assistant at the time, discussed ideas for comics with his brother and friends. Cham's brother, Jaime, suggested there should be a comic about grad school "because that's when the real pain begins". Cham had no formal art training and had never tried drawing comics before but his comic was accepted. Cham created the website a few weeks later. Cham continued the strip while completing his PhD and while as an instructor in mechanical engineering at Caltech, then in July 2005, left this work to become a full-time cartoonist.
Originally, the strip was drawn in black-and-white, eventually became grayscale, and finally became color in June 2004.
The strip is free online and is also syndicated free to student newspapers, with Cham earning a living through book sales, merchandise, and giving lectures. 
Themes.
The title of the comic comes from an old joke about becoming a Ph.D., which explains that "B.S." stands for "bullshit", "M.S." stands for "More of the Same" (or "More Shit"), and "Ph.D." stands for "Piled Higher and Deeper".
The comic follows the lives of graduate students and their professors. Reviewer Sara Coelho said "the comic deals with everyday frustrations of life in the lab – procrastination, dealing with advisers, serving on committees, lack of inspiration". Comics deal with the isolation of graduate work.
Cham's comics have also been on real-world research, such as a five-comic series following a visit to CERN.
Characters.
"Piled Higher and Deeper" introduced its main characters early in its run, and their personalities have remained fairly constant during the strip's several years of publication. In the strip's first few seasons, the characters were clearly Stanford University students, though the number of school-specific references and jokes has decreased since. 
Cham has said that while the character are not based on real people, he was inspired by colleagues, classmates, and his brother's friends.
Parodies.
One of Cham's recurring themes is to re-cast an item of popular culture in the grad-school milieu. Upon several occasions, the strip has included spoofs of popular movies, like "The Thesis" ("The Matrix"), "Raiders of the Lost Dissertation" ("Raiders of the Lost Ark"), "I, Grad Student" (a mixture of the book and movie "I, Robot"), and "Summer days" ("Summer Nights"). In addition, Cham has parodied television programs like "The Jerry Springer Show," among others.
Jorge Cham has also parodied Newton's laws of motion as "Newton's 3 Laws of Graduation". According to the strip these laws of graduation were superseded by Einstein's "Special Theory of Research Inactivity", much as Newton's actual laws were superseded by Einstein's Special Theory of Relativity.
Another series of strips takes up the modern debate about the proper use of the term "irony".
The strip has also included several adaptations of Shakespeare as well as several propaganda posters. Captions for the latter include "This man does research for "you!"", "When you procrastinate... Someone is watching!" and "Women in grad school... Support your local female geek."
Cham has also released two song parodies, purportedly sung by Tajel, in MP3 format: "Closer to fine" (cf. Indigo Girls) and "Who will grade your work" ("Who Will Save Your Soul").
Reception.
The comic resonates with graduate students. As of 2011, the strip's website received 7 million visitors each year, and a 2017 article reported that it received 6 million visitors a year. As of 2009, Cham had sold more than 46,000 books.
Books.
Six PhD comic books have been published so far. These are collections of the PHD Comic strips, and some books also contain bonus material:
Movie adaptations.
The PHD Movie.
In March 2011, Jorge Cham started filming a movie based on the comic series. The film production was a collaboration between Cham and a theater group at the California Institute of Technology. In fall 2011, the film was released on selected academic campuses. A trailer of the movie was released to the Piled Higher and Deeper website on June 8, 2011. After about a year of various campus screenings around the world, the movie became available for purchase on DVD or streaming on April 15, 2012. A columnist for Nature wrote: "the film puts the plight of the PhD student on the big screen, giving student audiences a chance to laugh at themselves... the film tackles some of the negative aspects of pursuing a PhD and a science career... "The PhD Movie" raises a question that crosses many students' minds: why bother? The answer it provides resonates with the audience: Everybody is here because they want to be here ... You have to embrace the things you're passionate about.'" 
The PHD Movie 2: Still in Grad School.
The sequel to the first movie was shot in the Caltech campus. The budget of $163,000 was provided by almost Kickstarter backers. It was released in September 2015; the comedy relates to a research team seeking a key molecule in a cutthroat environment for jobs and grants.
Lectures.
Cham gives lectures based on his comic. A 2009 article wrote that "the popularity of his keynote lectures... are enough to make even the most distinguished professor green with envy." His first lecture was at Massachusetts Institute of Technology in 2005 and was entitled "The Power of Procrastination".