Introduction: The term electronic commerce (e-commerce) refers to a business model that allows companies and individuals to buy and sell goods and services over the Internet. E-commerce operates in four major market segments and can be conducted over computers, tablets, smartphones, and other smart devices. Nearly every imaginable product and service is available through ecommerce transactions, including books, music, plane tickets, and financial services such as stock investing and online banking. As such, it is considered a very disruptive technology. E-commerce is the process of buying and selling tangible products and services online. It involves more than one the process of buying and selling tangible products and services online. It involves more than one party along with exchange of data or currency to process to transaction. It is part of the greater industry that is known as electronic business (e-business), which involves all of the processes required to run a company online. E-commerce has helped businesses (especially those with a narrow reach like small businesses) gain access to and establish a wider market presence by providing cheaper and more efficient distribution channels for their products or services. Target supplemented its brick-and-mortar presence with an online store that allows customers to purchase everything from clothes and coffeemakers to toothpaste and action figures right from their homes. 

Different types of E- Commerce: E-commerce involves buying and selling of products and services by businesses and consumers through an electronic medium. Broadly, e-commerce is classified into four categories: business to business or B2B (Cisco ), business to consumer or B2C (Amazon), consumer to consumer or C2C (eBay) and Business-to-Government (B2G). Business-to- business e-commerce involves agreements between the businesses and businesses. Distribution management, inventory management, channel management, supplier management and payment je management are some of the areas in which B2B applications are widely used. In Bangladesh, bgmea.com.bd, bizbangladesh.com are examples of B2B platforms. B2C commerce involves e- commerce between businesses and the consumers. This form of e-commerce involves the purchase of books or any form of consumer goods. It also includes purchase of software, e-books, games, songs as well as e-banking. ajkerdeal.com, bdbazar.com, daraz.com, bajna.com are some examples of B2C. Advantages of B2C platforms to companies are reduced operating costs, bigger outreach, globalisation, customer convenience and knowledge management. Consumer-to-consumer e- commerce involves transactions between individual consumers. For instance, online auction, peer- to-peer system for money or file exchange can be classified as forms of C2C e-commerce. In Bangladesh bikroy.com, clickbd.com are examples of C2C platforms. B2G is usually used for licensing process, public purchasing and other government operations. B2G e-commerce is rather insignificant when compared to the other three forms. However, B2G can be one of the driving forces for running the public sector known as e-Governance.

Components of E-Commerce: A wide range of technologies is used in e-commerce that includes electronic data interchange (EDI), electronic mail (e-mail), electronic funds transfer (EFT). In case of Electronic Data Interchange (EDI) there needs to be an agreement between trading partners. EDI is a standard method for exchanging business data. E-mail and fax are also forms of EDI. In Bangladesh small, medium and big enterprises have taken up e-business platforms. When compared to developed countries, developing countries have a higher potential for improving the business structure and raise productivity by using e-commerce as a medium. M-Commerce (Mobile Commerce) and F-Commerce (Facebook Commerce) are very popular in today's e-business world. Over the years, the number of online transactions has been on the rise. According to BTRC officials the number of internet subscribers in Bangladesh had crossed 80 million in 2017. At present there are approximately 2,000 e-commerce sites and 50,000 Facebook-based outlets delivering almost 30,000 products a day. Currently, 80 per cent of the online sales are taking place in Dhaka, Chattogram and Gazipur.

Advantages: The e-commerce industry in Bangladesh is an emerging industry. This sector is steadily growing and attaining competitiveness. The local e-commerce companies which have been in the market since inception of the e-commerce industry should be given protection. Simultaneously, foreign investments are required in this sector. The payment procedures offered by e-commerce sites need to be made more secure. Low-cost, high-speed internet needs to be ensured in the rural areas. The e-commerce industry needs to put more emphasis on delivery logistics and customer service. Immediate action to ensuring consumers' rights needs to be taken since a regulatory authority is not present to prevent consumers from being cheated and given low quality or date-expired products.

Disadvantages: Although the e-commerce sector has grown over the years, there remain a number of obstacles. Some of the key challenges are net neutrality, high-speed net, parcel delivery logistics and assurance of quality products. Foreign players also pose competition and risk to local start-ups. The sector suffers from lack of logistics and sound transportation system that restrict e-commerce trading to expand. Transportation system affects the delivery of products. Challenges also persist in the logistics sector. A large chunk of almost 65 per cent of the operations of the e-commerce companies takes place in the capital and Chattogram. The e-commerce companies fail to reach all parts of the country, including of course the rural areas, due to poor infrastructure and inability to access remote areas for lack of adequate transport facilities. In Bangladesh, in majority of the cases payment is made upon delivery. 80 per cent of the payments are done through cash-on-delivery method, whereas only 15-20 per cent are done through mobile payment gateways. Cash-on-delivery due to a lack of trust and the absence of a reliable and safe payment system. In addition, the number of credit and debit card users in the country is low, as a result many customers are unable to make online payments. The e-wallet system is expected to overcome this problem to some extent. bKash has partnered with the e-commerce ventures in the country and in addition, if banks also follow suit, it will be beneficial.

Conclusion: Despite the obstacles, the sector has a lot of potential and in the next few years, contribution of e-commerce to the country's GDP is likely to be significant. The government should be more forthcoming in supporting this sector as part of its Digital Bangladesh initiative.