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.