It's been around for so long it's almost hard to remember a time when ... live closer to a Walmart store or an Amazon locker, and if you care about controlling the exact delivery date.

Amazon and Walmart are two of the most popular big retailers ... While both services offer free shipping, free same-day delivery and free grocery delivery, they differ in cost and added benefits.

Walmart is taking its grocery delivery program nationwide, as the company steps up its battle with e-commerce behemoth Amazon. The world's largest retailer said Wednesday that it's expanding ...