An SSL certificate authenticates a website's identity and enables an encrypted HTTPS connection between the web server and the browser, activating the padlock icon. SSL certificates are essential for secure e-commerce sites as they prevent cybercriminals from intercepting data or impersonating legitimate websites.

eBay, Amazon, Flipkart, and Snapdeal follow the Business-to-Consumer (B2C) model, where businesses sell goods and services directly to end consumers through digital platforms. B2C is distinct from B2B (inter-business trade), C2C (consumer resale), and C2B (individuals selling to companies).

Increase in customer availability, 24/7 availability, and ease of comparison shopping are direct structural advantages of e-commerce. Credibility is not an inherent advantage — it depends on how an individual business manages customer service, security, and trust-building practices, and is not automatically conferred by operating as an e-commerce platform.

A digital wallet contains both a software component and an information component — the software provides security and encryption for personal data and transactions. Digital wallets are stored client-side, are easily self-maintained, and are fully compatible with most e-commerce websites, making them the standard tool for electronic transactions both online and at physical stores.

Business to Consumer (B2C) e-commerce allows businesses to sell goods or services directly to consumers without intermediaries, reducing costs and enabling direct interaction with customers. Common examples include online retail stores like Amazon and Flipkart where consumers purchase directly from the company's website.

C2C (Consumer-to-Consumer) e-commerce involves transactions directly between consumers, typically facilitated by a third-party platform — online auctions like eBay are a classic example. The other models — B2B (business to business), B2C (business to consumer), and C2B (consumer to business) — do not primarily involve consumer-to-consumer auction transactions.