MID Function is used to extract characters, words, phrases and even numbers from a cell. Mid refers to middle. It means that it can easily extract the middle part of the word or phrase. Assuming there is a cell with the text "71495865 What is Excel?" and you want to extract the middle part of the text "What is Excel". You can do so using the MID function. Here is how.
The RIGHT Function works in a similar way as the MID function. The difference, the RIGHT function picks up text from the right to the left. It is useful if you are trying to extract number at the end of the text in a cell. One example is the postal code which consist of a certain number of digits. Unlike the MID function, the RIGHT formula only has 2 parts, because it always starts from the right so there is no need to have the starting position. For example, if the postal code in A1 is the last 6 digits, you just have to enter the formula as (without quotes) "=RIGHT(A1,6)".
The LEFT function is the direct opposite of the RIGHT function. It extracts text or number from the left to the right. This function can be easily replace by the MID function. Just enter the number 1 in the starting position and you would have replicated the LEFT function using the MID function.