There are a lot of different ways to pack and ship items. When an item is packed, it can be packed in a box, poly mailer, or envelope. The boxes do not have to be new. Amazon or Walmart boxes can be used to ship something out to a friend or family member, just make sure that there are no barcodes on the box and that all stickers with your personal information are taken off. I ship something, I like to use poly mailers if the items are under one pound because it can fit in the mailbox much easier and it saves money. Boxes can add weight to an item making it more expensive to ship. If an item is being shipped and that item is over 2 pounds it is best to place it in a box since it is probably bigger. Items over 2 pounds are best shipped with UPS because that is the cheapest carrier for that weight. When shipping, you want to make sure the postage matches the actual weight of the item. If an item was to be shipped incorrectly, the person receiving the package would have to pay the postage that the sender did not. If the postage on a label says 15.9 ounces it is very important that the sender weights that item to make sure it is 15.9 ounces or under. If the items weigh more than that, then the sender will need to add postage. If a sender sells something online and does not put enough postage on the package, some companies such as eBay will just take it out of the sender's earnings or charge their PayPal account for the extra postage.
Several carriers can be used when it comes to shipping. FedEx, UPS, and USPS are all carriers used when an item is shipped. USPS is the post office and is viewed as the fastest method of shipping. FedEx and UPS have their own stores and have different guidelines than USPS. They all serve the same purpose but have different guidelines, which is interesting. With USPS and FedEx, postage is based on weight. UPS postage is based on both the weight and size of the box. If a small item is shipped in a large box with UPS, then the sender will have to pay more in postage because of the size of the box. After an item is shipped, tracking usually starts showing that day or early the next day. The person receiving the package can expect their package to be delved within 5-7 days of it being shipped.