The term voice refers to the form of a verb that shows whether the subject of a sentence does an action or has an action done to it. Active voice describes a sentence in which the subject performs the action expressed by the verb. Passive voice refers to a sentence in which the subject receives the action stated by the verb. Using these two types of voice, therefore, allows the writer to convey or emphasize ideas in different ways. In other words, the choice of the active or passive voice in writing will depend on the exact idea the writer wants to convey or emphasize.

So when exactly should you use the active voice? You can use the active voice when your aim is to draw attention to the doer of the action: when your focus is on who or what is responsible for the action being reported. For example, if you want to draw attention to the spectacular performance of Messi in a football match, you can’t simply say that “three goals were scored in the match.” You want to say that “Messi scored all the three goals that gave his team the victory in the match.”

Other important uses of the active voice are:

I. It allows you to use fewer words. In summarizing, for example, you use the active voice as a method of reducing words.

II. It helps to make your writing more concise and efficient.

III. The active voice enables you to create a faster-moving narrative, which makes your narrative more engaging to the reader.

IV. The active voice makes your writing more direct and vigorous. The use of active verbs simplifies the report or narrative since the reader can easily learn who is doing what.

V. The active voice also helps you to persuade with words: this is of critical importance in copywriting which is all about using words to persuade your prospects to take definite action. The use of action verbs makes your writing persuasive and engaging.

VI. The use of the active voice is also useful when your aim is to connect with your audience through your web content, for instance. Active sentences help to convey your message in a way that readers can quickly and easily digest.

The passive voice, on the other hand, has its many uses as well. You can use the passive voice when your aim is to emphasize the action rather than the actor.

With the passive voice you can easily report actions or incidents when the doer of the action is still unknown or unnecessary at the time of reportage. Sometimes it is necessary to report a sad incident such as a robbery, an arson, a burglary or a murder, even if the culprit is still unknown. The report can simply read: “The house was burgled and many valuable items were carted away. The burgers were still unknown at the time of this report. However, the incident has been reported to the police, and investigation has begun.”

For a detailed audio-visual explanation of the active and passive voice, watch the following video lecture:
https://www.youtube.com/watch?v=ADGsyQlAw9M