Six months into the year, and e-commerce trends upward as a growing choice for shoppers.

According to eMarketer, annual global e-commerce sales are set to double over the next four years, to about $4.1 trillion. In 2016, all e-commerce sales worldwide hit $1.9 trillion, up from $1.5 trillion in 2015.

Just take a look at Amazon’s shares, which briefly topped $1,000 at the end of May, marking a milestone moment in the tech giant’s 1,340 percent run over the past decade.

Here are some of the e-commerce trends so far:

Brick-and-Mortar Stores Closing

Retail stores closures are nothing new. However, the rate at which it is happening this year is staggering. Brokerage firm Credit Suisse recently released a report stating that more than 8,600 stores will close in 2017. In comparison, 2,056 stores closed in 2016, according to the report. This is mainly due to the rise in e-commerce.

Revamping the Online Experience

Retail customers continue demanding convenience and ease of use while shopping online. As a result, retailers are revamping their websites to ensure a great customer experience, which has not always been the case in the past. For example, lost revenue caused by incomplete transactions due to broken websites amounted to almost $4 trillion, in 2016.

Additionally, the online shopping experience includes reducing the number of steps for customers, from selecting a product, to purchasing and delivery (same-day in some cases).

Rise of the Machine

Companies such as Amazon and Facebook are employing updated chatbots, a form of artificial intelligence that makes employee tasks more efficient, deliver data and information to customers, and drive more conversions through deep learning processes. This is resulting in more customer engagement and real-time ordering.

Facebook’s Emergence in e-Commerce

Having branded itself as an all-in-one platform for e-commerce, the social platform is making it easier for its users to shop for products without leaving its site via Facebook Shop. Additionally, brands are utilizing Facebook Live to show off their products in real-time to potential customers.