A telephone is a telecommunications device that permits two or more users to conduct a conversation when they are too far apart to be heard directly. A telephone converts sound, typically and most efficiently the human voice, into electronic signals that are transmitted via cables and other communication channels to another telephone which reproduces the sound to the receiving user.
A common short form of the term is phone, which came into use almost immediately after the first patent was issued.
In 1876, Alexander Graham Bell was the first to be granted a United States patent for a device that produced clearly intelligible replication of the human voice at a second device. This instrument was further developed by many others, and became rapidly indispensable in business, government, and in households.
The essential elements of a telephone are a microphone (transmitter) to speak into and an earphone (receiver) which reproduces the voice in a distant location. In addition, most telephones contain a ringer to announce an incoming telephone call, and a dial or keypad to enter a telephone number when initiating a call to another telephone. The receiver and transmitter are usually built into a handset which is held up to the ear and mouth during conversation. The dial may be located either on the handset or on a base unit to which the handset is connected.
The transmitter converts the sound waves to electrical signals which are sent through a telephone network to the receiving telephone, which converts the signals into audible sound in the receiver or sometimes a loudspeaker. Telephones are duplex devices, meaning they permit transmission in both directions simultaneously.
The first telephones were directly connected to each other from one customer’s office or residence to another customer’s location. Being impractical beyond just a few customers, these systems were quickly replaced by manually operated centrally located switchboards. These exchanges were soon connected together, eventually forming an automated, worldwide public switched telephone network.
For greater mobility, various radio systems were developed for transmission between mobile stations on ships and automobiles in the mid-20th century. Hand-held mobile phones were introduced for personal service starting in 1973. In later decades, their analog cellular system evolved into digital networks with greater capability and lower cost.
Convergence has given most modern cell phones capabilities far beyond simple voice conversation. Most are smartphones, integrating all mobile communication and many computing needs.
Thanks to Wikipedia:
It is a pleasure to participate again in the Week Photo Challenge. The theme of this week is <a href="http://Focus“>Pure.
My contribution to the subject are these precious and sleeping twins. No one would doubt its purity, yet…
This is my contribution to this Week Photo Challenge: Partners
These are a group of “castellers”, that is, a group of people who build human “castles”. I think this perfectly reflects the concept of partners.
A castell (castle) is a human tower built traditionally in festivals at many locations within Catalonia. At these festivals, several colles castelleres (group of people who do these towers) often succeed in building and dismantling a tower’s structure. On November 16, 2010, castells were declared by UNESCO to be amongst the Masterpieces of the Oral and Intangible Heritage of Humanity.
A castell is considered a success when stages of its assembling and disassembling, can be done in complete succession. The assembly is complete once all castellers have climbed into their designated places, and the enxaneta climbs into place at the top and raises one hand with four fingers erect, in a gesture said to symbolize the stripes of the Catalan flag. The enxaneta then climbs down the other side of the castell, after which the remaining levels of castellers descend in highest-to-lowest order until all have reached safety.
Aside from the people who climb to form the upper parts of the tower, others are needed to form the pinya, or bottom base of the castell, to sustain its weight. Members of the pinya (most often men) also act as a ‘safety net’ if the tower structure collapses, cushioning the fall of people from the upper levels. It is not uncommon—when not in competitions—for other colles to assist in the pinya when a small colla is attempting a specially demanding structure in terms of people needed.
More info: Wikipedia
Harsh and cold
autumn holds to it our naked trees:
If only you would free, at least, the sparrows
from the tips of your fingers
and release a smile, a small smile
from the imprisoned cry I see.
Sing! Can we sing
as if we were light, hand in hand
sheltered in shade, under a strong sun?
Will you remain, this way
stoking the fire, more beautiful than necessary, and quiet?
and the distant light is our only consolation —
that one, which from the beginning
has, little by little, been flickering
and is now about to go out.
Come to me. Closer and closer.
I don’t want to know my hand from yours.
And let’s beware of sleep, lest the snow smother us.
by Walid Khazindar
Walid Khazindar was born in 1950 in Gaza City. He is considered one of the best Palestinian poets; his poetry has been said to be “characterized by metaphoric originality and a novel thematic approach unprecedented in Arabic poetry.” He was awarded the first Palestine Prize for Poetry in 1997.
This is my contribution to this Week Photo Challenge: Spare
During one of my walks around the city, with camera in hand, I walked into a store that unfortunately no longer exists. Among other things, it caught my attention these colorful shelves. Dozens of towels of different colors, all correctly positioned. I think here are really plenty of spare towels.
I’ve always been interested in geometrically distributed collections of objects and I thought these shelves well deserved a photo.
Weekly Photo Challenge. Earth
I liked the words of this Weekly Challenge: “As far as we currently know, our planet is unique in its ability to sustain life. We are an island in an unimaginably huge universe… I have always regarded nature with reverence…”.
In my opinion, our planet deserves all our respect. We live by what the Earth offers to us. It is extremely unwise to continue mistreating our planet. Our future and, above all, those who succeed us, depends on it.
Montserrat is a multi-peaked mountain located near the city of Barcelona, in Catalonia. It is part of the Catalan Pre-Coastal Range. The Caribbean island of Montserrat was named by Christopher Columbus after the mountain.
It is well known as the site of the Benedictine abbey, Santa Maria de Montserrat, which hosts the Virgin of Montserrat sanctuary and which is identified by some with the location of the Holy Grail in Arthurian myth.
“Montserrat” literally means “saw (serrated, like the common handsaw) mountain” in Catalan. It describes its peculiar aspect with multitude of rock formations which are visible from a great distance. The mountain is composed of strikingly pink conglomerate, a form of sedimentary rock.
Weekly Photo Challenge. Dinnertime
This week, the challenge asks for an image inspired by dinnertime. This is mine.
I was taking pictures when I found this beautiful specimen at its dinner time. I suddenly remembered that my dinner time had also come…
Marina Port neighborhood is around the current Paseo de la Zona Franca next to the harbor.
The Port of Barcelona has a 2000-year history and great contemporary commercial importance as one of Europe’s ports in the Mediterranean, as well as Catalonia‘s largest port, tying with Tarragona. It is divided into three zones: Port Vell (the Old Port), the commercial/industrial port and the logistics port (Barcelona Free Port).
The Port Vell area comprises two marinas or yacht harbors, a fishing port, a maritime station for ferries travelling to the Balearic Islands and other destinations in the Mediterranean and other stations or landing areas for cruise ships, and it abuts the industrial port.
More info: Wikipedia
Anselm Kiefer (born March 8, 1945) is a German painter and sculptor. He studied with Joseph Beuys and Peter Dreher during the 1970s. His works incorporate materials such as straw, ash, clay, lead, and shellac.