The minijack 3.5mm is a popular connector used primarily for headphones although its functionality is much more varied.

It consists of a maximum of three connecting parts being the largest so-called mass or negative polarity and two of smaller size and located farther end of the connector, called living or positive that correspond to each channel, such three-part plug can transmit signals in two different channels, also known as stereo signals. It also exists in a mono minijack but version composed of only two parts, a body and a living or positive.

The term VGA (Video Graphics Array or Video Graphics Adapter) is a graphics display system for PCs developed by IBM. VGA has become one of the standards for the PC image. In text mode, VGA provides a resolution of 720 by 400 pixels. In graphics mode, the resolution is either 640 by 480 (with 16 colors) or 320 by 200 (with 256 colors). The color palette is 262,144.Unlike earlier graphic standards for PCs - MDA, CGA, EGA and VGA - uses analog signals rather than digital signals. Since its introduction in 1987, several other standards have been developed that offer greater resolution and more colors (SVGA, XGA ...), but VGA remains the denominator used. All personal computers manufactured today still have support VGA, and possibly some other more advanced connection.

UTP cable is standard twisted pair is referred by its acronym UTP (Unshiedld Twiested Pair/Unshielded Twisted Pair). The major advantages of this cable are its low cost and ease of handling. Its main disadvantages are a higher error rate compared to other cable types and their limitations to work at high distances without regeneration. FTP is a type of cable caracteriza that each twisted pair is uniformly during creation. A comprehensive screening of all pairs is performed by a apantallante outer sheet. This technique allows to have similar characteristics to the shielded cable. STP is characterized by that each pair is covered with a metal mesh, in the same way that the coaxial cables, and the set of pairs is coated with a sheet apantallante. Referenced frequently with their acronym STP (Shield Twisted Pair/Shielded Twisted Pair)

(DHCP stands for Dynamic Host Configuration Protocol, in Spanish "protocol Dynamic Host Configuration") is a network protocol that allows clients to obtain an IP network configuration parameters automatically. It is a protocol for client/server where a server usually has a list of dynamic IP addresses and will allocate these customers as they are left freeKnowing at all times who has been in possession of that IP, how long it has had and who has been assigned later.

When we talk about RJ45 ("Registered Jack" 45) we refer to a telecommunications network interface for wired connection of voice and data equipment.

This connector has 8 pins or connections and may have a specific category depending on the data transfer speed and bandwidth (category 5e, 6, etc.)

The common application is their use in Ethernet network cables under TIA/EIA-568-B standard that defines the arrangement of pins (pinout), but can also be used for other applications.

- Direct pin diagram:

EIA-568A
Pin No.1: WHITE-GREEN
Pin No.2: GREEN
Pin No.3: WHITE-ORANGE
Pin No.4: BLUE
Pin No.5: WHITE-BLUE
Pin No.6: ORANGE
Pin No.7: WHITE-BROWN
Pin No.8: BROWN

EIA-568B
Pin No.1: WHITE-ORANGE
Pin No.2: ORANGE
Pin No.3: WHITE-GREEN
Pin No.4: BLUE
Pin No.5: WHITE-BLUE
Pin No.6: GREEN
Pin No.7: WHITE-BROWN
Pin No.8: BROWN

- Schematic of crossed pins:

The crossover cable has one end with EIA-568A scheme and the other one with EIA-568B.

We can find 3 types of jack connector, monaural TS connector (tip-sleeve), TRS (tip-ring-sleeve) and TRRS stereo plug (tip-ring-ring-sleeve) which is used in most mobile devices, tablets, MP3 etc ...
We can difference these 3 types of connectors according to their diameter:

1. 6.35 mm jack connector or TS.
2. 3.5mm minijack connector or TRS, is the most common, usually used in headphone's output of portable devices.
3. 2.5mm jack connector or TRRS.

It consists of a maximum of three connecting parts being called the largest mass or negative polarity and two smaller size located more towards the end of the connector,
The called positive that correspond to each channel, such three-part plug can transmit signals in two separate channels, also known as stereo signals. There's a mono version, consisting of only two parts, a negative and a positive.

A. Protector
B. Stem
C. Ring
D. Tip
E. Kindred
F. Ring (Signal Right)
G. Tip (Signal Left)

The Wifi technology is a wireless communication mechanism between devices. This technology allows you to connect devices such as computers, laptops, mobile etc... to the Internet or communicate with the devices themselves.

Applications can be several, among the most common are the access points, ideal for giving and sharing a connection signal to multiple devices. It is the typical configuration of a home user.
Repeater, ideal to repeat and amplify weak signal.

The power and range between devices basically depends on the antenna and its hardware.

The wireless signals work under a unified standard regulations, the standard that is based on the IEEE 802.11. These include IEEE 802.11b, IEEE 802.11g and IEEE 802.11n working at 11 Mbit/s, 54 Mbit/s and 300 Mbit/s, respectively.
Being any device with a standardized protocol such technology can connect to another using the same technology, making it a kind of universal connection.

The wireless networks are characterized by the ease and convenience of making connections in infrastructure, since it is not necessary to perform network cable installations.
it also allows connecting a lot of devices to a single node.

Depending on the quality and type, network cables are classified into categories that help us know the characteristics of them.

The categories of network cables most commonly used are:

- Category 5
- Category 5e
- Category 6
- Category 6
- Category 7

As can be seen, category 5e (enhanced or improved) and category 6A (Augmented), are an improvement of categories 5and 6, respectively, which it has improved the top speed and bandwidth.

The higher the category, the higher the speed of maximum data, the maximum 100 meters distance as its standard.

You can see a table which shows the 5 categories, where V is the maximum velocity, D is the maximum and MHz frequency which can work away.