Radio initially began as a medium of home entertainment. Today radio is highly mobile, stretching beyond the four walls of our home and becoming a part of everybody's life. It often plays in the background whilst we jog, read, drive and work and some radio stations now broadcast across the world wide web.

For these reasons and more, radio is a very influential advertising medium. However, just like all marketing tools it has notable strengths and weaknesses. An awareness of these strengths and weaknesses will allow the advertiser to use the tool most effectively.

Radio presents many strengths, the major being the fact that it is a low cost mass media. Given the low costs associated with reaching a high percentage of the market, the cost of achieving an effective campaign is often lower than other medias. This is due to the greater reach and frequency attainable within a given budget.

Whilst radio reaches a mass market, a characteristic usually associated with a high percentage of waste coverage, radio actually allows you to be relatively segmented. Advertisements can be targeted towards particular groups of consumers according to the programming and geographic coverage of the radio station. The genre of music attracts a higher percentage of a certain market over others. By having an understanding of the stations genre, geographical coverage and programming format, messages can be targeted at times when they will have the highest likelihood of reaching the desired market.

Radio allows you to be very flexible with your message given the short production time required and the live format of stations. This enables the consumer to react quickly to market changes and take advantage of opportunities presented.

When planning a radio campaign it is important to hold an awareness of the weaknesses characteristic to the medium. The major drawback of radio is its inability to provide a visual image. Radio does not allow the advertiser to:

• Show the product;
• Demonstrate the product;
• Use any type of visual appeal; or
• Visualise information.

Radio, like most multimedia productions, is a fleeting message with an external rate so it does not allow the receiver to control the rate in which they digest the message.

Once the strengths and weaknesses are apparent, the advertiser should plan to use a support media whose characteristics counteract the weaknesses of radio. This is the technique of developing a media mix. Radio relies of the consumer to place visual images to the voice and words they hear, a process known as 'Image Transfer'. The ideal medium should be visual such as television. Image transfer then allows the receiver to take the message they hear and match it to the vision they recalled from the television commercial. This describes how radio can be beneficial as reinforcement of television and vice versa.

There is no doubt that radio is a very effective advertising medium, but as with any other medium, it works best when used within a planned media mix. As with all media, an advertiser has to look at how it is consumed in relation to what the campaign objectives are.