Talk radio is a radio format containing discussion about topical issues. Most shows are regularly hosted by a single individual, and often feature interviews with a number of different guests. Talk radio typically includes an element of listener participation, usually by broadcasting live conversations between the host and listeners who "call in" (usually via telephone) to the show. Listener contributions are usually screened by a show's producer(s) in order to maximize audience interest and, in the case of commercial talk radio, attract advertisers. Generally, the shows are organized into segments, each separated by a pause for advertisements; however, in public or non-commercial radio, music is sometimes played in place of commercials to separate the program segments. Variations of talk radio include conservative talk, hot talk, progressive talk, and sports talk.

Talk radio is not limited to the AM band. "Non-commercial" usually referred to as "public radio", which is located in a reserved spectrum of the FM band, also broadcasts talk programs. Commercial all-talk stations can also be found on the FM band in many cities across the US. These shows often rely less on political discussion and analysis than their AM counterparts, and often employ the use of pranks and "bits" for entertainment purposes. In the United States and Canada, Satellite Radio broadcasters, such as SIRIUS, offer uncensored "free-wheeling" original programming, such as The Howard Stern Show and The Jay Thomas Show, formerly featured on terrestrial, government-censored radio. ABC News&Talk is an example of 'rebagging' for the digital airwaves shows featured on their terrestrial radio stations.

Starting around 2005, the technology for Internet-based talk-radio shows became cost effective. Now, it is possible for an individual to use a variety of services to host an Internet-based talk-radio show without investing any of their own capital.