If you're connecting a telephone or an analog modem
to your Plain Old Telephone System, or your POTS system,
then you're probably using this RJ11 connector.
This is what we technically call a six-position two-conductor
connector.
That means there are six places for wires inside
of this connector, but we're really only using
two of those conductors.
As you can see in this cable--
that it has this RJ11 connection at the end.
You might find some of the RJ11 cables
that you're using for your modem or your telephone actually
have four wires inside of them with four different conductors.
That six-position four conductor is technically
an RJ14 connector, but it has exactly the same connector
on the end.
And we often use these cables interchangeably.
With a separate set of conductors
or separate set of wires inside of this cable,
we're able to use this single cable for dual line
use for someone who might have two telephones on their desk.
Here's the connection that is inside
the modem or inside of the device that's connecting
to this RJ11 connection.
And you can see the two conductors
that are inside of that connector
when you plug in the RJ11 modular connector.
A connector that's a little bit wider than an RJ11 is an RJ45.
This is the type of connector you commonly
see associated with a wired Ethernet connection.
This is an eight-position eight-conductor connection,
which means we have all eight of those connectors and all eight
of those wires that are being used inside of that cable.
This is also similar to a format you
might see called an RJ48C, which has an eight-position four
conductor.
Those are commonly seen with T1 or wide area network
connections.
An RS-232 connection stands for Recommended Standard 232.
This is a serial connection type that has literally
been around since 1969.
And it has been around so long because it's
able to connect to so many different kinds of devices.
Before there was USB-type connectivity,
we commonly used RS-232 to connect our mouse
connections, our printers, our networks, and other devices
as well.
These days, RS-232 is commonly used
as a configuration port on a switch
or a router or a firewall, and it's
plugging into a serial interface on a laptop
or another computer.
The 25-pin version of RS-232 is usually referred to as a DB25.
This nine-pin connection, which is a bit more modern,
you'll sometimes hear referred to as a DB9.
But, technically, it's the smaller style
of D-subminiature interface, which is the E side.
So you may see this nine-pin connection being
referred to as DB9 or DE9.
It's really referring to exactly the same connection.
A very common type of coaxial cable connection
is a BNC connection.
The B in BNC stands for Bayonet, which
is the style of cable that plugs in and then twists to lock.
And you can see the locking mechanism on the cable
right here.
The N and the C in BNC stands for Paul Neill,
who is at Bell Labs, and Carl Concelman, who is at Amphenol.
They designed this particular connection
and called it the BNC connection.
As I mentioned, this is commonly seen
on coax connections for wide area networks, especially
DS3-type WAN links.
Because this BNC connection is connecting coax together,
you're usually working with a type of media that's
a little more bulky and a little more rigid,
and it can be more difficult to work with.
But because you're using this bayonet-type connection that
twists in and locks in place, you
can be sure that nobody can accidentally pull out
one of these connections because you must untwist this
a quarter of the way before you're able to pull it out
of that connection.
Another type of connector that does not come disconnected
very easily is an F connection.
It's commonly used on cable television
or cable-modem-type connections.
You can see that the connection itself is threaded.
So to plug in this coax connection, which is commonly
RG6 or RG59, you are threading this onto the connection.
So this makes it very difficult to accidentally disconnect an F
connection because you first must
untwist all of those threads before the cable can
be removed.
USB is some of the most common connectors we use these days.
And for USB 1.1 and 2.0, we use this style of connector.
The standard A plug has the same form factor
as other USB standards, although there
may be a different number of pins inside of a USB 1.1
or USB 2.0 plug.
The standard B plug for these versions of USB
is this squared-type plug.
And this is usually one that you would
plug into a printer or some other peripheral.
For smaller mobile devices, you commonly
see the mini B plug or the micro B plug
being used for USB-type connections.
The USB 3.0 and higher connections
have similar but slightly different types of connectors.
The USB 3.0 standard B plug, you can see,
still maintains that square shape,
but there's additional areas on the top
of that particular plug.
The standard A plug looks and feels
exactly the same as the older versions, but, as I mentioned,
this version has some additional pins on the inside.
And you can see the micro B plug has changed quite a bit.
We have some additional pins that
have been added on if you're using this newer
style of USB micro B.
A newer standard connector for USB is the USB-C connector.
You can see these are relatively small interfaces, as you
can see by the side of this laptop,
and the USB interface doesn't have a top or bottom.
You can plug it in either way, and it
works exactly the same regardless
of how you connect it.
If you're using a mobile device from Apple,
you may be using a Lightning connector.
This is a proprietary Apple connector
that has eight different pins that you would use
to connect your mobile device.
This has a number of advantages over the Micro-USB
that you might find on other mobile devices.
One advantage is that it has a higher power output,
so you can charge those mobile devices even faster.
Just like USB-C, the Lightning connector also
does not have a top or bottom.
So you can simply plug it in, and it's
going to work either way.
This is also a simpler design than Micro-USB,
and it's designed to be more durable than those connectors
as well.
In an earlier video, we looked at all of the different SCSI
interfaces that you might run into.
And in the older legacy style of SCSI,
you can certainly connect to those devices
using many, many different types of interfaces.
Here's an example of a 68-pin legacy
SCSI connection that's on a motherboard.
And you can see the difference between a SATA
drive and those connections, the PATA drive and the very large
PATA data connection, and then the SCSI connection
on the drive at the bottom.
Modern SCSI drives use a serial attached SCSI drive connection
very similar to the SATA-type connections
you would see on those drives, although these interfaces
are slightly different than the SATA drive that you might see.
And if you have internal serial attached SCSI devices,
you may have an internal high-density connector
such as this one that might be used for those serial attached
SCSI drives.
If you're plugging in an external device with SATA,
you're probably using an eSATA connection.
An eSATA connector has ears on the side and a single square
that's in the middle of the connector.
This is a little different than the internal SATA-type
connection that you would have inside of a computer, where
the inside is more of an L shape,
and there's a single ear that's along the outside.
On the inside of our desktop computers,
we may be connecting older peripherals
or maybe connecting our fans to something
like these four-pin Molex connectors.
We call this a Molex connector because it was created
by the Molex Connector Company.
Technically, this is also an AMP MATE-N-LOK connector,
and it provides 12-volt and 5-volt power
for these internal peripherals.
So if you're connecting older storage
drives or the internal fans or other components inside
of your system, you might be using this Molex connector
to provide that power.
The power for Molex is usually provided directly
from the power supply.
This power supply is a bundle of cables
with other connectors on the end for connection
to the motherboard, and you can see the four-pin Molex
connectors are there as well.