Sender-Message-Channel-Receiver Model of Communication
The sender-message-channel-receiver (SMCR) model of communication is an expansion of the Shannon-Weaver model of communication. David Berlo created this model, which separated Shannon and Weaver's linear model into clear parts, in 1960. It has been expanded upon by other scholars. Berlo described factors affecting the individual components in the communication making the communication more efficient. Background. Berlo's model of communication developed from Claude Shannon and Warren Weaver's mathematical model, which was first published in "Bell System Technical Journal" in 1948. The model was primary designed to  improve the technical communication, but was later widely applied in different fields of communication. According to the Shannon-Weaver model, communication includes the following concepts: sender, encoder, channel, decoder, receiver and feedback. Furthermore, there is also concept of "noise", which affects the communication process going through the channel and makes the message more difficult to understand by the receiver. Each of those concepts are defined as follows: Sender: the originator of message. Encoder: the transmitter which converts the message into signals (the way message is changed into signals, for example sound waves). Channel: the signal carrier or medium Decoder: the  reception place of the signal which converts signals into message. Decoding is done by the receiver when he gets the message. Receiver: the recipient of the message from the sender. He usually gives feedback to the sender in order to make sure that the message was properly received. Noise the message, transferred through a channel, can be interrupted by external noise (for instance, conversation may be interrupted by thunder or crowd noise). Feedback: The receiver can get an inaccurate message. This is why feedback from the receiver is important in case the message is not properly received. Furthermore, the noise  can also affect the decoding of the message by the receiver. Practical Example of Shannon-Weaver model of communication: Thomson made call to his assistant "come here I want to see you." During his call, noise appeared (transmission error) and his assistant received "I want" only. Again Assistant asked Thomson (feedback) "what do you want Thomson?" Berlo's model was first published in 1960 in the book entitled "El Proceso de la Comunicación" ("The Process of Communication"). The model includes four components to describe the communication process: sender, message, channel, and receiver, each of them affected by many factors. The  model also focuses on encoding and decoding, which happens before the sender sends the message and before the receiver receives the message respectively. The main feature from the previous Shannon-Weaver model is the focus on the purpose and objectives of communication. Berlo's model also includes verbal and non-verbal communications, and it considers the emotional aspects of the message. Components of the SMCR model. The SMCR model explains the various components in the communication process. The four basic components are sender (or source), message, channel and receiver. Sender. Sender is the source of the message or the person  who originates the message. The sender transfers the information using the following factors: An individual must possess excellent communication skills to make his communication effective and create an impact on the listeners. He should know how to speak and how pronounce a word correctly, where to take pauses and where to repeat, and so on. Similarly, if the receiver does not understand the message, the communication will be ineffective. The attitude of the sender and the receiver affects the message. The person's attitude towards the receiver and the environment changes the meaning and effect of the message. In this  context, knowledge is not the level of education. It is the clarity of the information which the sender wants to convey to the receiver. Familiarity with the subject of the message makes it easier to understand. Values, beliefs, religion, laws, rules and general understanding of society affect the sender's way of communicating the message. Culture refers to the cultural background of the sender or receiver. Message. The step of creating a message (also called encoding) is the transformation of thoughts into words that sender sends to receiver. It can be in the form of voice, audio, text, video or  other media. Any message comprises the following elements: Channel. Channel refers to the medium used to send the message. In mass communication technical machines might be used as a channel like telephone, internet, etc. But in general communication, the five senses of a human being is the channel for the communication flow and it affects the effectiveness of the channel: Receiver. Receiver is the person who gets the message and tries to understand what the sender actually wants to convey and then responds accordingly. This is also called as decoding. Berlo's model believes that the effective communication can be  achieved if the sender and the receiver are on the same level. The message might not have the same effect as intended if the receiver and sender are not similar. The receiver must also have a very good listening skill. Other factors are similar to that of the sender: Berlo's model was further developed in 1973 by W. Schramm, who used a relational model instead of linear. Schramm also used the effects and effects analysis components from Berlo's model and suggested an interaction component in relation with active, selective and manipulative audience. He argued that the most dramatic  change in communication theory in the last 40 years has been the abandonment of the idea of passive audience. Audience is a full partner in the process of communication.