Ethos, Pathos, and Logos are modes of persuasion used to convince audiences.  They are also referred to as the three artistic proofs (Aristotle coined the terms), and are all represented by Greek words. 

Ethos or the ethical appeal, means to convince an audience of the author’s credibility or character.

An author would use ethos to show to his audience that he is a credible source and is worth listening to. Ethos is the Greek word for “character.” The word “ethic” is derived from ethos.

Ethos can be developed by choosing language that is appropriate for the audience and topic (this also means choosing the proper level of vocabulary), making yourself sound fair or unbiased, introducing your expertise, accomplishments or pedigree, and by using correct grammar and syntax.

During public speaking events, typically a speaker will have at least some of his pedigree and accomplishments listed upon introduction by a master of ceremony.

Pathos or the emotional appeal, means to persuade an audience by appealing to their emotions.

Authors use pathos to invoke sympathy from an audience; to make the audience feel what what the author wants them to feel. A common use of pathos would be to draw pity from an audience. Another use of pathos would be to inspire anger from an audience, perhaps in order to prompt action. Pathos is the Greek word for both “suffering” and “experience.” The words empathy and pathetic  are derived from pathos.

Pathos can be developed by using meaningful language, emotional tone, emotion evoking examples, stories of emotional events, and implied meanings. 

Logos or the appeal to logic, means to convince an audience by use of logic or reason.

To use logos would be to cite facts and statistics, historical and literal analogies, and citing certain authorities on a subject. Logos is the Greek word for “word,” however the true definition goes beyond that, and can be most closely described as “the word or that by which the inward thought is expressed" and, "the inward thought itself" (1). The word “logic” is derived from logos.

Logos can be developed by using advanced, theoretical or abstract language, citing facts (very important), using historical and literal analogies, and by constructing logical arguments.

In order to persuade your audience, proper use of Ethos, Pathos, and Logos is necessary.

Examples of Ethos, Logos and Pathos:

Example of Ethos: 

“Woz and I started Apple in my parents garage when I was 20. We worked hard, and in 10 years Apple had grown from just the two of us in a garage into a $2 billion company with over 4000 employees. We had just released our finest creation — the Macintosh — a year earlier, and I had just turned 30...

During the next five years, I started a company named NeXT, another company named Pixar, and fell in love with an amazing woman who would become my wife. Pixar went on to create the worlds first computer animated feature film, Toy Story, and is now the most successful animation studio in the world. In a remarkable turn of events, Apple bought NeXT, I returned to Apple, and the technology we developed at NeXT is at the heart of Apple's current renaissance. And Laurene and I have a wonderful family together.”

Stanford Commencement Speech by Steve Jobs. June 12, 2005.

Example of Pathos:

"I am not unmindful that some of you have come here out of great trials and tribulations. Some of you have come fresh from narrow jail cells. And some of you have come from areas where your quest -- quest for freedom left you battered by the storms of persecution and staggered by the winds of police brutality. You have been the veterans of creative suffering. Continue to work with the faith that unearned suffering is redemptive. Go back to Mississippi, go back to Alabama, go back to South Carolina, go back to Georgia, go back to Louisiana, go back to the slums and ghettos of our northern cities, knowing that somehow this situation can and will be changed."

I Have a Dream by Martin Luther King Jr. August 28th, 1963.

Example of Logos:

"However, although private final demand, output, and employment have indeed been growing for more than a year, the pace of that growth recently appears somewhat less vigorous than we expected. Notably, since stabilizing in mid-2009, real household spending in the United States has grown in the range of 1 to 2 percent at annual rates, a relatively modest pace. Households' caution is understandable. Importantly, the painfully slow recovery in the labor market has restrained growth in labor income, raised uncertainty about job security and prospects, and damped confidence. Also, although consumer credit shows some signs of thawing, responses to our Senior Loan Officer Opinion Survey on Bank Lending Practices suggest that lending standards to households generally remain tight."