E-commerce or eCommerce is the contraction of "Electronic Commerce". It is the purchase of services and goods through the internet. There are various types of E-Commerce such as Business to Business (B2B) and Business to Consumer (B2C) which involve purchase by bank transfer or credit card. An example is eBay and Amazon as sales platforms.
Today there are several specific CMS (Content Management Systems) for E-Commerce such as PrestaShop, Drupal Commerce, WooCommerce and Magento that allow the creation of online sales portals with the possibility of managing the purchase of goods or services through a shopping cart and finalize the sale directly by credit card or prepaid card.
To avoid security problems we rely on the Transport Layer Security (SSL / TLS) protocol which in combination with the HTTP protocol, allows us to have a new data transmission protocol in an encrypted form called HTTPS which makes an E-Commerce website more secure.