## 1 Introduction  
The outbreak of COVID-19 transformed the daily activities of human beings from living, traveling, and working to social interactions. Like many other sectors, the education system experiences grave implications involving students, instructors, and institutions around the globe. In the midst of worldwide COVID-19 lockdowns, educational institutes have been closed for formal face-to-face education leading to digital transformation and the unprecedented rise of online learning. Online learning, also called e-learning, is learning through synchronous or asynchronous environments involving the use of internet-enabled mobile devices such as mobile phones, laptops, tablets, etc. [1]. The transition from traditional education to online education is not possible overnight and several challenges may hinder this transition. Despite its advantages, the challenges of transition may impair the full potential of online education. Several studies investigate the effectiveness and advantages of online education over conventional teaching methods. The advantages include overall flexibility, extended reach of teaching, accessibility, and non-confinement of time and place as well as the pace of learning. On the other hand, several serious challenges pose serious threats to e-learning over conventional classroom teaching methods. The limitations include the availability of communication technology infrastructure, high cost of equipment and devices, limited technical know-how of teachers and learners, and cultural change needed for successful and effective online education. The COVID-19 pandemic affected the education system globally with conventional education activities suspended. Billions of students from different educational and training courses were not able to attend the in campus teaching sessions. Most of the educational and teaching institutions around the world switched their teaching-learning process to different e-learning platforms and communication media. Not only does online education provide significant advantages in the teaching and learning process, in the present scenario of the COVID-19 pandemic, it served as a backbone for the education system globally. While switching from face-to-face conventional teaching to e-learning, it must be ensured that the e-learning method should be at least a feasible alternative if not better than the traditional education. As some studies such as [2; 3; 4] argue that, even with the present technological revolution which demands the adoption of e-learning, the conventional face-to-face in campus sessions cannot be replaced fully. Furthermore, face-to-face teaching is a cornerstone for most educational institutions. According to the famous Bloom's Taxonomy, the framework for the classification of educational outcomes classifies learning outcomes in six domains: knowledge, comprehension, application, analysis, synthesis, and evaluation [5]. Most modern educational institutions rely on [PERSON]'s taxonomy for the learning outcome process. Considering the above-mentioned educational outcomes and adoption of e-learning, there is a significant need to evaluate the effectiveness and challenges of e-learning. This study presents the analyses of the sentiments of students, teachers as well as other stakeholders gathered from Twitter. The tweets from different entities related to education such as parents, students, teachers, and other stakeholders will be covering most of the aspects of online education. Such aspects include advantages, disadvantages, challenges, and difficulties faced in adopting the e-learning approach. Sentiment analysis, a field in text analysis, holds great potential to extract and analyze the sentiments, and opinions of people regarding a specific topic, idea, personality, or institution, thereby revealing its pros and cons with respect to common people.