Hepcat said that Onion Routing is a way to prevent spying when using wireless Internet. Thanks Hepcat. I haven’t wrapped my head around this information yet — but it’s interesting. This info is from Wikipedia. 

The goal of onion routing (OR) is to protect the privacy of the
sender and recipient of a message, while also providing protection for
message content as it traverses a network. Onion routing accomplishes
this according to the principle of Chaum’s mix cascades:
messages travel from source to destination via a sequence of proxies
("onion routers"), which re-route messages in an unpredictable path. To
prevent an adversary from eavesdropping on message content, messages
are encrypted between routers. The advantage of onion routing (and mix
cascades in general) is that it is not necessary to trust each
cooperating router; if one or more routers are compromised, anonymous
communication can still be achieved. This is because each router in an
OR network accepts messages, re-encrypts them, and transmits to another
onion router. An attacker with the ability to monitor every onion
router in a network might be able to trace the path of a message
through the network, but an attacker with more limited capabilities
will have difficulty even if he or she controls one or more onion
routers on the message’s path.

Onion routing does not provide perfect sender or receiver anonymity
against all possible eavesdroppers—that is, it is possible for a local
eavesdropper to observe that an individual has sent or received a
message. It does provide for a strong degree of unlinkability,
the notion that an eavesdropper cannot easily determine both the sender
and receiver of a given message. Even within these confines, onion
routing does not provide any absolute guarantee of privacy; rather, it
provides a continuum in which the degree of privacy is generally a
function of the number of participating routers versus the number of
compromised or malicious routers.

The primary innovation in onion routing is the concept of the
routing onion. Routing onions are data structures used to create paths
through which many messages can be transmitted. To create an onion, the
router at the head of a transmission selects a number of onion routers
at random and generates a message for each one, providing it with symmetric keys
for decrypting messages, and instructing it which router will be next
in the path. Each of these messages, and the messages intended for
subsequent routers, is encrypted with the corresponding router’s public key.
This provides a layered structure, in which it is necessary to decrypt
all outer layers of the onion in order to reach an inner layer.

The onion metaphor describes the concept of such a data structure.
As each router receives the message, it "peels" a layer off of the
onion by decrypting with its private key, thus revealing the routing
instructions meant for that router, along with the encrypted
instructions for all of the routers located farther down the path. Due
to this arrangement, the full content of an onion can only be revealed
if it is transmitted to every router in the path in the order specified
by the layering.

Once the path has been specified, it remains active to transmit data
for some period of time. While the path is active, the sender can
transmit equal-length messages encrypted with the symmetric keys
specified in the onion, and they will be delivered along the path. As
the message leaves each router, it is encrypted using a different key,
and thus is not recognizable as the same message.