Critical thinking is defined as disciplined, clear, rational, and evidence-based thinking. It involves assessing the validity and worth of ideas. Critical thinking is important for success in higher education and careers as it allows students to better understand concepts, analyze different viewpoints, and develop problem-solving skills. In the 21st century, critical thinking is important for effective learning and instruction as it involves asking questions, gathering information, developing reasoned conclusions, and communicating effectively. Various tools like storytelling, YouTube, podcasts, and social media can be used to promote critical thinking in teaching by engaging students and encouraging creativity.