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How Spotify Changed the Music Industry
Before Spotify: The Era of Physical Media and Downloads
Marcelo Serafim
May 34 min read


The History of the United States: From Colonial Times to the End of the Civil War
Colonial Beginnings
Marcelo Serafim
May 34 min read


Dinosaurs: A Journey Through Time and Their Eras
Dinosaurs, the awe-inspiring reptiles that dominated Earth for over 160 million years, captivate our imagination with their colossal...
Marcelo Serafim
May 15 min read


Cargill: A Global Agribusiness Giant, Its Family Legacy, and Controversies
Cargill, Incorporated, founded in 1865 by William Wallace Cargill, stands as the largest privately held company in the United States, with revenues reaching $165 billion in 2022. Starting as a single grain storage warehouse in Conover, Iowa, at the end of the American Civil War, Cargill has grown into a multinational agribusiness titan, operating in 66 countries and employing over 160,000 people. The company’s core operations span trading, purchasing, and distributing agricul
Marcelo Serafim
Apr 237 min read


Dreams: A Journey Through Science and Spirituality
Dreams, those enigmatic experiences that unfold in our minds during sleep, have fascinated humanity for millennia. They are a universal...
Marcelo Serafim
Apr 225 min read


The Rise of Talent as a Service: Redefining Workforce Solutions
In an era of rapid technological advancement and shifting economic paradigms, the concept of "Talent as a Service" (TaaS) has emerged as a transformative approach to workforce management. TaaS refers to the practice of accessing skilled professionals on-demand, typically through a flexible, scalable model, rather than maintaining a permanent staff. This paradigm allows companies to tap into a global pool of expertise—be it developers, marketers, or executives—without the over
Marcelo Serafim
Apr 75 min read


How Earth Gets Its Seasons
Have you ever wondered why we experience different seasons—spring, summer, fall, and winter? It’s not because of how far Earth is from the Sun. Instead, seasons happen because Earth is tilted on its axis . This tilt changes how sunlight reaches different parts of the planet throughout the year.
Marcelo Serafim
Apr 74 min read


William Shakespeare: The Bard of All Time
1. Introduction William Shakespeare is widely regarded as the greatest playwright in the English language and one of the most influential...
Marcelo Serafim
Apr 74 min read


The Tariffs Imposed by the Trump Administration: A Deep Dive into Global Trade and Potential Outcomes
In early 2025, the Trump administration rolled out a series of aggressive tariffs on imports from numerous countries, marking a significant shift in U.S. trade policy. On February 1, 2025, President Donald Trump imposed a 25% tariff on most goods from Canada and Mexico, alongside a 10% tariff on Chinese imports, citing national security concerns over illegal immigration and the flow of fentanyl. By April 2, dubbed "Liberation Day" by Trump, he declared a national emergency un
Marcelo Serafim
Apr 76 min read


Traveling: From Departure to Destination
Traveling can be an exciting and sometimes stressful experience, involving multiple steps from leaving your home to arriving at your final destination. Understanding the process helps ensure a smooth journey and minimizes unexpected challenges. This article will take you through each stage of travel, from hailing a cab or Uber to checking into your hotel and asking for directions.
Marcelo Serafim
Mar 254 min read


The Big 4: An Overview of the World's Largest Accounting Firms
The term "Big 4" refers to the four largest professional services firms in the world that specialize in audit, tax, consulting, and advisory services. These firms are Deloitte, PricewaterhouseCoopers (PwC), Ernst & Young (EY), and KPMG. They dominate the global accounting industry and provide services to major corporations, governments, and financial institutions worldwide.
Marcelo Serafim
Mar 253 min read


The Pope
The Pope is the head of the Roman Catholic Church and the Bishop of Rome. He is considered the spiritual leader of over 1.3 billion Catholics worldwide. The position of the Pope, also known as the papacy, dates back to Saint Peter, who is traditionally recognized as the first Pope and one of Jesus Christ’s apostles. The Pope’s role is to provide guidance, preserve church doctrine, and act as a representative of Christ on Earth.
Marcelo Serafim
Mar 254 min read


What is PTSD?
Post-Traumatic Stress Disorder (PTSD) is a serious mental health condition that can develop after experiencing or witnessing a traumatic event. It affects a person’s ability to function in daily life, often causing distressing symptoms such as flashbacks, nightmares, and severe anxiety. While PTSD is commonly associated with military veterans, it can affect anyone who has gone through a life-threatening or deeply disturbing experience.
Marcelo Serafim
Mar 254 min read


The Legal System Roles
The legal and judiciary systems are essential to maintaining justice, order, and fairness in society. These systems are composed of...
Marcelo Serafim
Mar 254 min read


(Teacher's Version) What Is a Business Consultancy Company?
Before you start, what is a consultant? what do they do? A business consultancy company is a professional service firm that provides...
Marcelo Serafim
Mar 205 min read


Common Health Problems: Symptoms and Treatments
Health is one of the most valuable aspects of human life, yet many people experience common health problems that can affect their daily activities and overall well-being. While some conditions are mild and temporary, others may require medical intervention. Understanding the symptoms and available treatments can help individuals manage their health effectively. This article explores some of the most common health problems, their symptoms, and possible treatments.
Marcelo Serafim
Mar 136 min read


(Teacher's Version) Soccer: The World's Most Popular Sport
Before starting the class, do you like soccer? Do you have a favorite national and international team? Who are you a fan of and why?...
Marcelo Serafim
Mar 105 min read


The Potential Threat of a Nuclear Holocaust: A Detailed Exploration
The specter of a nuclear holocaust looms as one of humanity’s most existential threats, a cataclysmic event capable of obliterating civilizations and rendering the planet uninhabitable. Since the detonation of the first atomic bombs in 1945 over Hiroshima and Nagasaki, the world has lived under the shadow of nuclear proliferation. Today, nine countries—United States, Russia, China, France, the United Kingdom, Pakistan, India, Israel, and North Korea—possess nuclear arsenals,
Marcelo Serafim
Mar 66 min read


Walmart: The Rise to Retail and Employment Dominance
Walmart’s journey to becoming the world’s largest retailer and private employer is a tale of vision, scale, and relentless efficiency. Founded in 1962 by Sam Walton in Rogers, Arkansas, the company began as a single discount store aimed at offering low prices to rural Americans. Walton’s philosophy of "everyday low prices" (EDLP) resonated with cost-conscious shoppers, setting the stage for explosive growth. By 2025, Walmart operates over 10,500 stores across 24 countries, em
Marcelo Serafim
Feb 265 min read


How to Compose the Selling Price of a Product or Service (Pricing)
Determining the selling price of a product or service is one of the most critical decisions a business owner must make. It directly impacts profitability, market competitiveness, and customer perception. Pricing too high might alienate potential buyers, while pricing too low could undermine your revenue or signal poor quality. To strike the right balance, several factors must be meticulously considered, including costs, market demand, competition, and perceived value. This ar
Marcelo Serafim
Feb 245 min read
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