Header tags are an important on-page SEO factor because they’re used to communicate to the search engines what your website is about. Search engines recognize the copy in your header tags as more important than the rest. This starts with your h1 and works its way down in importance to the h2, h3 and so on. These tags will help support the overall theme or purpose of your page.

Header tags are part of the website’s code and thus are not visible on the site’s pages. 

The alt text describes what’s on the image and the function of the image on the page. So if you have an image that’s used as a button to buy product X, the alt text would say: “button to buy product X”.

The alt tag is used by screen readers, the browsers used by blind and visually impaired people, to tell them what is on the image.

Each image should have an alt text. Not just for SEO purposes but also because blind and visually impaired people otherwise won’t know what the image is for.

Most browsers these days DO NOT display “Alt Tags” so unless you can view page code you won’t know they are missing.

Schema markup is code (semantic vocabulary) that you put on your website to help the search engines return more informative results for users.

Schema tells the search engines what your data means, not just what it says.

Schema.org, the website for schema markup, was created by a collaborative team from Google, Bing, and Yahoo.

Schema code is placed with the website’s “Header” section which is an area of code not visible on website’s pages. The only way to see is if you can view page source code. 

A good XML sitemap is a roadmap to all important pages of a website. This roadmap guides Google to all main content on a website. Having an XML sitemap can be beneficial for SEO, as Google can retrieve essential pages of a website very fast, even if the internal linking of a site isn’t flawless.

You want Google to crawl every important page of your website. But it can happen pages don’t have any – internal – links to them, which will make them hard to find. You can use an XML sitemap to make sure Google can find and crawl all pages you deem essential on your website. An XML sitemap contains all important pages of a site to help Google determine the structure of it:

An XML Sitemap is a website page of code that is visible to search engines but NOT site visitors. If a developer created a XML sitemap it should be very small hyperlinked text (XML Sitemap) located in the bottom footer area of the website. Although visible it is small and often people don’t know to look for it or understand it’s function. 

A good HTML sitemap is a website page which is roadmap to all important pages of a website which is easily visible and useful when trying to locate a link that’s hard to find.

An HTML sitemap (as opposed to an XML sitemap) is often mentioned as being useful for SEO. They certainly are if you use them wisely (and especially Bing seems to like them at times).

If a developer created a HTML sitemap it should be very small hyperlinked text (HTML Sitemap) located in the bottom footer area of the website. Although visible it is small and often people don’t know to look for it or understand it’s function. 

Is your completed website being submitted to major search engines, Google, Bing & Yahoo (BING & Yahoo submission is the same) with a compliant XML sitemap?

The only way to know for sure is if the submission was done through your search engine accounts or developer provided screen shots of submission.