A "dialer" is a component that can automatically make calls to phone numbers. It is used to avoid the work of manually calling numbers and also spares the employees to actually wait to see if a person answers their phone.
An efficient dialer can increase the productivity of a team which needs to call contacts on the phone significantly.
Advanced dialer products also automate all kinds of business processes that are related to the sales or service function where the dialer is used.
Many different terms are used to describe dialers, like predictive dialers, adaptive dialers, power dialers, dynamic dialers, progressive dialers, automatic dialers and auto dialers. These different terms can be confusing and as you'll see if you keep reading, they are not very clear or well-defined. The terms used do not matter as much as understanding which workflows and processes can be enabled by which dialer product.
Jargon buster: predictive vs power vs dynamic etc
What is a predictive dialer?
The term "predictive" is used if the mechanism to decide how many outbound calls are made and when to start making another outbound call uses past call and employee availability data to "predict" how many call attempts are needed to ensure that employees are utilized well.
What is an adaptive dialer?
"Adaptive" is used to describe a dialing mechanism that changes depending on circumstances and past data. Hence, it is also a "predictive" dialer. Any predictive dialer that is useful in practice should of course adapt its dialing behavior if the real number of calls answered or connected to employees changes.
What is a power dialer?
The term "power" dialer in practice just means that it is possible setting simple controls regarding the number of outbound calls made per agent. Typically, it stands for automated dialing without any form of adaptive or predictive mechanism. The word "power" seems to have been introduced for marketing purposes.
How to choose a dialer nowadays?
For many decades, dialers were separated closed systems like PBXs and office telephone systems. Therfore, dialers often were a sort of siloed system that could not be integrated more deeply into the other workflows and business processes. This was a consequence of the type of technology available at the time and the system architecture limitations that resulted.
That is why there was a high focus on the differences of the available dialing mechanisms. Of course, some of these products allowed some interfaces for uploading lists of contact numbers and made it possible to use the dialer in a real-world sales or service process. But these capabilities were rudimentary.
Nowadays, the "dialer" part is just one component and the main advantage of the product actually lies in the integration and process mechanisms that make it possible to automate and enable all kind of complex work flows. Also, a modern product is oftentimes not only focussed on call lists. Frequently, tasks other than speaking to a person on the phone also need to be scheduled and distributed to the right available employee. To sum that up, a dialer is actually just a special case of a what can be called an "automated task distributor".
What are the component parts of a modern dialer or task distributor?
A modern task distributor will include the following components: scheduler, availability/presence handler, queuing mechanisms, mechanism to input/upload lists, list ordering mechanisms, task outcome model, event handlers, integration interfaces for other systems, user interface for employees, user interface for administrators, data extraction and data analytics (to produce performance metrics). In addition, a dialer as a special kind of task distributor will have the ability to determine the phone line state for the employees and the ability to dial out through the public telecoms network - note that these last two components are the only part that is related to "dialing" or "calling", all other components are present in any task distributor.
You can find an illustration and description of the logical architecture of how a dialer is used here.