Dodge asks, "How is it that my friend is able to use free wireless hotspots from their laptop?".
These days mobile phones, laptops, and tablets commonly come with a built-in wireless adapter, but the type of the adapter will generally vary based on when you've purchased the device; these days you'll likely be looking at an 802.11ac card, though in the past you'd probably have either an 802.11n or 802.11g. These standards are generally based on speed, but some will also affect range (a 2.4ghz signal will penetrate walls easier than a 5ghz one).
You can also buy wireless network adapters for your computers (laptops and pc's alike); these can come as USB adapters or PCI adapters (or in the case of older laptops, PCMCIA adapters or ExpressPort adapters). They're relatively affordable (ranging from $10-40+) and generally easy to install with systems having plug and play capabilities you simply insert the adapter and start your computer.
Plenty of stores, businesses, shopping centers, and fast food restaurants offer free wifi, you simply just tell your device to look for open networks and it'll locate anything that's available and ask if you'd like to connect to the network.
It's safe to say though that most of the residential networks that you'll find are various people who've left their home internet connections open to make life easier on themselves (not having a password means that you can connect without a password like a general open hotspot).
There are some safety concerns to keep in mind however; by connecting to someones network without their permission you're basically stealing from their connection, and its also possible that as you're you're connecting to their network to utilize their internet that they can "sniff" your traffic on their network, or they could access any open network shares that you may have on your computer.
