Search engines find and catalog web pages through spidering (also known as webcrawling) software. Spidering software "crawls" through the internet and grabs information from websites which is used to build search engine indexes. Unfortunately, not all search engine spidering software works the same way, so what gives a page a high ranking on one search engine may not necessarily give it a high ranking on another. Note that rather than waiting for a search engine to discover a newly created page, web designers can submit the page directly to search engines for cataloging.
Hey Ted, thanks for the great questions! The peak times refer to your particular time zone, if you are targeting an audience that resides in the same zone as you. You can also use tools to find out when most of your audience is online. For example, Facebook has this built into their Page Insights. For Twitter, you can use https://followerwonk.com/. Many social posting tools also offer this functionality.