0:00:01.744,0:00:05.210
If you're connecting a[br]telephone or an analog modem

0:00:05.210,0:00:09.380
to your Plain Old Telephone[br]System, or your POTS system,

0:00:09.380,0:00:12.170
then you're probably[br]using this RJ11 connector.

0:00:12.170,0:00:16.370
This is what we technically call[br]a six-position two-conductor

0:00:16.370,0:00:17.180
connector.

0:00:17.180,0:00:20.150
That means there are six[br]places for wires inside

0:00:20.150,0:00:22.340
of this connector, but[br]we're really only using

0:00:22.340,0:00:24.020
two of those conductors.

0:00:24.020,0:00:25.880
As you can see in this cable--

0:00:25.880,0:00:28.910
that it has this RJ11[br]connection at the end.

0:00:28.910,0:00:31.880
You might find some[br]of the RJ11 cables

0:00:31.880,0:00:34.970
that you're using for your[br]modem or your telephone actually

0:00:34.970,0:00:39.080
have four wires inside of them[br]with four different conductors.

0:00:39.080,0:00:42.200
That six-position four[br]conductor is technically

0:00:42.200,0:00:46.190
an RJ14 connector, but it has[br]exactly the same connector

0:00:46.190,0:00:46.970
on the end.

0:00:46.970,0:00:49.940
And we often use these[br]cables interchangeably.

0:00:49.940,0:00:52.130
With a separate[br]set of conductors

0:00:52.130,0:00:54.890
or separate set of wires[br]inside of this cable,

0:00:54.890,0:00:57.680
we're able to use this[br]single cable for dual line

0:00:57.680,0:01:01.250
use for someone who might have[br]two telephones on their desk.

0:01:01.250,0:01:03.050
Here's the connection[br]that is inside

0:01:03.050,0:01:06.050
the modem or inside of the[br]device that's connecting

0:01:06.050,0:01:07.820
to this RJ11 connection.

0:01:07.820,0:01:09.920
And you can see[br]the two conductors

0:01:09.920,0:01:11.750
that are inside[br]of that connector

0:01:11.750,0:01:16.190
when you plug in the[br]RJ11 modular connector.

0:01:16.190,0:01:21.790
A connector that's a little bit[br]wider than an RJ11 is an RJ45.

0:01:21.790,0:01:23.680
This is the type of[br]connector you commonly

0:01:23.680,0:01:27.020
see associated with a[br]wired Ethernet connection.

0:01:27.020,0:01:30.520
This is an eight-position[br]eight-conductor connection,

0:01:30.520,0:01:34.420
which means we have all eight of[br]those connectors and all eight

0:01:34.420,0:01:38.360
of those wires that are being[br]used inside of that cable.

0:01:38.360,0:01:40.510
This is also similar[br]to a format you

0:01:40.510,0:01:44.800
might see called an RJ48C,[br]which has an eight-position four

0:01:44.800,0:01:45.640
conductor.

0:01:45.640,0:01:48.790
Those are commonly seen[br]with T1 or wide area network

0:01:48.790,0:01:50.380
connections.

0:01:50.380,0:01:55.240
An RS-232 connection stands[br]for Recommended Standard 232.

0:01:55.240,0:01:57.970
This is a serial connection[br]type that has literally

0:01:57.970,0:02:00.700
been around since 1969.

0:02:00.700,0:02:03.220
And it has been around[br]so long because it's

0:02:03.220,0:02:06.490
able to connect to so many[br]different kinds of devices.

0:02:06.490,0:02:08.919
Before there was[br]USB-type connectivity,

0:02:08.919,0:02:12.400
we commonly used RS-232[br]to connect our mouse

0:02:12.400,0:02:15.850
connections, our printers, our[br]networks, and other devices

0:02:15.850,0:02:16.750
as well.

0:02:16.750,0:02:18.910
These days, RS-232[br]is commonly used

0:02:18.910,0:02:21.160
as a configuration[br]port on a switch

0:02:21.160,0:02:23.320
or a router or a[br]firewall, and it's

0:02:23.320,0:02:26.050
plugging into a serial[br]interface on a laptop

0:02:26.050,0:02:27.325
or another computer.

0:02:27.325,0:02:33.180
The 25-pin version of RS-232 is[br]usually referred to as a DB25.

0:02:33.180,0:02:36.280
This nine-pin connection,[br]which is a bit more modern,

0:02:36.280,0:02:39.220
you'll sometimes hear[br]referred to as a DB9.

0:02:39.220,0:02:41.530
But, technically,[br]it's the smaller style

0:02:41.530,0:02:45.130
of D-subminiature interface,[br]which is the E side.

0:02:45.130,0:02:47.440
So you may see this[br]nine-pin connection being

0:02:47.440,0:02:49.960
referred to as DB9 or DE9.

0:02:49.960,0:02:54.000
It's really referring to[br]exactly the same connection.

0:02:54.000,0:02:57.160
A very common type of[br]coaxial cable connection

0:02:57.160,0:02:59.150
is a BNC connection.

0:02:59.150,0:03:01.870
The B in BNC stands[br]for Bayonet, which

0:03:01.870,0:03:05.680
is the style of cable that plugs[br]in and then twists to lock.

0:03:05.680,0:03:08.170
And you can see the locking[br]mechanism on the cable

0:03:08.170,0:03:09.100
right here.

0:03:09.100,0:03:13.030
The N and the C in BNC[br]stands for Paul Neill,

0:03:13.030,0:03:17.200
who is at Bell Labs, and Carl[br]Concelman, who is at Amphenol.

0:03:17.200,0:03:19.060
They designed this[br]particular connection

0:03:19.060,0:03:20.890
and called it the[br]BNC connection.

0:03:20.890,0:03:23.230
As I mentioned, this[br]is commonly seen

0:03:23.230,0:03:26.230
on coax connections for wide[br]area networks, especially

0:03:26.230,0:03:28.210
DS3-type WAN links.

0:03:28.210,0:03:31.455
Because this BNC connection[br]is connecting coax together,

0:03:31.455,0:03:34.570
you're usually working[br]with a type of media that's

0:03:34.570,0:03:36.760
a little more bulky and[br]a little more rigid,

0:03:36.760,0:03:38.990
and it can be more[br]difficult to work with.

0:03:38.990,0:03:41.950
But because you're using this[br]bayonet-type connection that

0:03:41.950,0:03:44.380
twists in and[br]locks in place, you

0:03:44.380,0:03:46.750
can be sure that nobody[br]can accidentally pull out

0:03:46.750,0:03:49.780
one of these connections[br]because you must untwist this

0:03:49.780,0:03:52.300
a quarter of the way before[br]you're able to pull it out

0:03:52.300,0:03:54.580
of that connection.

0:03:54.580,0:03:57.220
Another type of connector that[br]does not come disconnected

0:03:57.220,0:03:59.170
very easily is an F connection.

0:03:59.170,0:04:01.630
It's commonly used[br]on cable television

0:04:01.630,0:04:03.700
or cable-modem-type connections.

0:04:03.700,0:04:06.250
You can see that the[br]connection itself is threaded.

0:04:06.250,0:04:09.340
So to plug in this coax[br]connection, which is commonly

0:04:09.340,0:04:14.140
RG6 or RG59, you are threading[br]this onto the connection.

0:04:14.140,0:04:16.930
So this makes it very difficult[br]to accidentally disconnect an F

0:04:16.930,0:04:18.700
connection because[br]you first must

0:04:18.700,0:04:21.550
untwist all of those[br]threads before the cable can

0:04:21.550,0:04:23.740
be removed.

0:04:23.740,0:04:26.990
USB is some of the most common[br]connectors we use these days.

0:04:26.990,0:04:31.390
And for USB 1.1 and 2.0, we[br]use this style of connector.

0:04:31.390,0:04:34.270
The standard A plug has[br]the same form factor

0:04:34.270,0:04:36.460
as other USB standards,[br]although there

0:04:36.460,0:04:40.540
may be a different number[br]of pins inside of a USB 1.1

0:04:40.540,0:04:42.790
or USB 2.0 plug.

0:04:42.790,0:04:45.220
The standard B plug for[br]these versions of USB

0:04:45.220,0:04:46.967
is this squared-type plug.

0:04:46.967,0:04:48.550
And this is usually[br]one that you would

0:04:48.550,0:04:51.340
plug into a printer or[br]some other peripheral.

0:04:51.340,0:04:53.560
For smaller mobile[br]devices, you commonly

0:04:53.560,0:04:56.770
see the mini B plug[br]or the micro B plug

0:04:56.770,0:04:59.740
being used for[br]USB-type connections.

0:04:59.740,0:05:02.380
The USB 3.0 and[br]higher connections

0:05:02.380,0:05:06.060
have similar but slightly[br]different types of connectors.

0:05:06.060,0:05:08.830
The USB 3.0 standard[br]B plug, you can see,

0:05:08.830,0:05:10.720
still maintains[br]that square shape,

0:05:10.720,0:05:13.120
but there's additional[br]areas on the top

0:05:13.120,0:05:14.620
of that particular plug.

0:05:14.620,0:05:16.690
The standard A plug[br]looks and feels

0:05:16.690,0:05:19.630
exactly the same as the older[br]versions, but, as I mentioned,

0:05:19.630,0:05:22.630
this version has some[br]additional pins on the inside.

0:05:22.630,0:05:25.305
And you can see the micro B[br]plug has changed quite a bit.

0:05:25.305,0:05:26.680
We have some[br]additional pins that

0:05:26.680,0:05:29.230
have been added on if[br]you're using this newer

0:05:29.230,0:05:32.690
style of USB micro B.

0:05:32.690,0:05:37.500
A newer standard connector for[br]USB is the USB-C connector.

0:05:37.500,0:05:40.440
You can see these are relatively[br]small interfaces, as you

0:05:40.440,0:05:42.900
can see by the side[br]of this laptop,

0:05:42.900,0:05:45.480
and the USB interface[br]doesn't have a top or bottom.

0:05:45.480,0:05:47.580
You can plug it in[br]either way, and it

0:05:47.580,0:05:49.410
works exactly the[br]same regardless

0:05:49.410,0:05:51.036
of how you connect it.

0:05:51.036,0:05:53.590
If you're using a mobile[br]device from Apple,

0:05:53.590,0:05:56.000
you may be using a[br]Lightning connector.

0:05:56.000,0:05:58.450
This is a proprietary[br]Apple connector

0:05:58.450,0:06:00.610
that has eight different[br]pins that you would use

0:06:00.610,0:06:02.510
to connect your mobile device.

0:06:02.510,0:06:05.620
This has a number of[br]advantages over the Micro-USB

0:06:05.620,0:06:08.230
that you might find on[br]other mobile devices.

0:06:08.230,0:06:11.230
One advantage is that it[br]has a higher power output,

0:06:11.230,0:06:14.260
so you can charge those[br]mobile devices even faster.

0:06:14.260,0:06:17.140
Just like USB-C, the[br]Lightning connector also

0:06:17.140,0:06:18.437
does not have a top or bottom.

0:06:18.437,0:06:20.020
So you can simply[br]plug it in, and it's

0:06:20.020,0:06:21.670
going to work either way.

0:06:21.670,0:06:24.520
This is also a simpler[br]design than Micro-USB,

0:06:24.520,0:06:27.130
and it's designed to be more[br]durable than those connectors

0:06:27.130,0:06:28.870
as well.

0:06:28.870,0:06:31.570
In an earlier video, we looked[br]at all of the different SCSI

0:06:31.570,0:06:33.400
interfaces that[br]you might run into.

0:06:33.400,0:06:36.040
And in the older[br]legacy style of SCSI,

0:06:36.040,0:06:38.140
you can certainly[br]connect to those devices

0:06:38.140,0:06:41.320
using many, many different[br]types of interfaces.

0:06:41.320,0:06:43.720
Here's an example[br]of a 68-pin legacy

0:06:43.720,0:06:46.240
SCSI connection that's[br]on a motherboard.

0:06:46.240,0:06:48.430
And you can see the[br]difference between a SATA

0:06:48.430,0:06:51.640
drive and those connections, the[br]PATA drive and the very large

0:06:51.640,0:06:54.460
PATA data connection, and[br]then the SCSI connection

0:06:54.460,0:06:57.410
on the drive at the bottom.

0:06:57.410,0:07:01.760
Modern SCSI drives use a serial[br]attached SCSI drive connection

0:07:01.760,0:07:04.070
very similar to the[br]SATA-type connections

0:07:04.070,0:07:06.680
you would see on those drives,[br]although these interfaces

0:07:06.680,0:07:10.460
are slightly different than the[br]SATA drive that you might see.

0:07:10.460,0:07:13.460
And if you have internal[br]serial attached SCSI devices,

0:07:13.460,0:07:15.960
you may have an internal[br]high-density connector

0:07:15.960,0:07:18.950
such as this one that might be[br]used for those serial attached

0:07:18.950,0:07:21.310
SCSI drives.

0:07:21.310,0:07:23.920
If you're plugging in an[br]external device with SATA,

0:07:23.920,0:07:26.550
you're probably using[br]an eSATA connection.

0:07:26.550,0:07:30.580
An eSATA connector has ears on[br]the side and a single square

0:07:30.580,0:07:32.750
that's in the middle[br]of the connector.

0:07:32.750,0:07:35.380
This is a little different[br]than the internal SATA-type

0:07:35.380,0:07:38.050
connection that you would have[br]inside of a computer, where

0:07:38.050,0:07:40.170
the inside is more[br]of an L shape,

0:07:40.170,0:07:44.450
and there's a single ear[br]that's along the outside.

0:07:44.450,0:07:46.610
On the inside of our[br]desktop computers,

0:07:46.610,0:07:48.710
we may be connecting[br]older peripherals

0:07:48.710,0:07:51.050
or maybe connecting[br]our fans to something

0:07:51.050,0:07:53.870
like these four-pin[br]Molex connectors.

0:07:53.870,0:07:56.360
We call this a Molex connector[br]because it was created

0:07:56.360,0:07:58.520
by the Molex Connector Company.

0:07:58.520,0:08:01.910
Technically, this is also[br]an AMP MATE-N-LOK connector,

0:08:01.910,0:08:04.460
and it provides 12-volt[br]and 5-volt power

0:08:04.460,0:08:07.390
for these internal peripherals.

0:08:07.390,0:08:08.950
So if you're connecting[br]older storage

0:08:08.950,0:08:12.370
drives or the internal fans[br]or other components inside

0:08:12.370,0:08:15.340
of your system, you might be[br]using this Molex connector

0:08:15.340,0:08:17.170
to provide that power.

0:08:17.170,0:08:19.690
The power for Molex is[br]usually provided directly

0:08:19.690,0:08:21.040
from the power supply.

0:08:21.040,0:08:23.380
This power supply is[br]a bundle of cables

0:08:23.380,0:08:25.600
with other connectors on[br]the end for connection

0:08:25.600,0:08:28.300
to the motherboard, and you[br]can see the four-pin Molex

0:08:28.300,0:08:30.960
connectors are there as well.