Secure Search Browser Hijacker
Secure Search is a type of potentially unwanted program. More specifically, it belongs to the family known as browser hijackers.
Potentially unwanted software will generally pose less of a threat to your overall system security compared to conventional malware, but it might assist in collecting data about your browsing habits, diminish your overall browsing experience or expose you to pages that may lead to the downloading of further malware on your system.
If you suddenly find that typing anything in your address bar to use your browser's default search engine, you see the text "Secure Search" after the query you are typing, or if your home page is replaced without your knowledge or consent with one "powered by Secure Search", you have the Secure Search browse hijacker on your system.
Browser hijackers, as their name suggests, change different parameters inside your browser. That usually includes your default search engine and home page. The trouble here is that this all happens without informing the user and without their consent.
This is why similar applications are classified as potentially unwanted. Additionally, with most browser hijackers, the search queries you feed into the modified search engine are intercepted, stored, and later commonly sold to third-party advertising networks to generate revenue for the author of the hijacker.
All of those behaviors combined make browser hijackers like Secure Search something you don't want on your system.
If you are wondering how you got it on your system in the first place, the most likely answer is "through a bundle installer". Those are software bundles containing multiple applications that are distributed through free download websites of less than spotless reputation.
Your best bet is to steer clear of similar download packages as they often have browser hijackers, adware, or similar potentially unwanted software bundled in them.