Page Titles
A Page Title is one of the most important on-page ranking factors and should be treated with care! Your page title tag shows up in Search Engine result pages. Search engines such as Google Yahoo, and Bing use the title tag for the page results.
Page Titles are usually around 50-60 characters long.
Meta Descriptions
Meta descriptions are HTML attributes that provide concise explanations of the contents of web pages. Search engines commonly use this to display a preview of the given page.
Meta Keywords
The meta tags are a very important part of the HTML code of your web page. They are read by the search engines but are not displayed as a part of your web page content. Usually they include a concise summary of the web page content and should include your relevant keywords.
Should be around 150 characters.
H1 Tag
The header tag is usually the title of a post, or other emphasised text on the page. It will usually be the largest text that stands out.
Should be no more than one sentence.
H2 Tag
The H2 tag is also a title tag however can be used as a subheading or to divide a page onto sections.
Images
Just like the visually impaired, search engines can’t see images on websites. Even if an image has text embedded within it, search engines are unable to crawl that text. So by not creating alt attributes for each and every image on your site, you lose a huge opportunity to be as visible as possible online.