AlgorithmInput is a PUP (Potentially Unwanted Program) that is being distributed via underhanded methods. The goal is to deliver the application onto the users' Mac devices without being noticed. To achieve this, various deceptive tactics can be employed. The most popular by far is known as bundling. It wrapping the intruder app inside the installation process of a more desirable software product. Users go and install this freeware application without knowing that another program has been included as a pre-selected choice unless they specifically look under the 'Custom' or 'Advanced' settings.
PUPs are created to generate monetary gains for their operators by carrying out intrusive activities on the device. AlgorithmInput is not an exception. In fact, it combines the functionalities of both adware and a browser hijacker. In practice, this means that the application is capable of delivering unwanted advertisements to the Mac, while also taking control over the user's Web browser. The shown advertising materials could take many forms - pop-ups, in-text links, banners, etc., but they all should be approached with caution. Engaging with the advertisements could lead users to be redirected to unsafe phishing pages, online scams, fake giveaways or other shady websites.
As for the browser, by changing the homepage, new tab page, and the default search engine, the PUP will try to generate artificial traffic towards its promoted address. Browser hijackers are a typical vehicle when it comes to promoting fake search engines that would otherwise be ignored by users completely. Fake engines cannot produce any search results by themselves as they simply lack that functionality. When a search is initiate it will be redirected to a legitimate engine such as Yahoo, Bing or Google.
And if these aren't enough red flags to consider removing any PUP immediately, keep in mind that such applications are almost always equipped with data-harvesting capabilities. They could access various browsing information (visited websites, conducted searches), device details (IP address, geolocation, ISP), or even try to collect payment information that has been saved into the affected browser.