Think CodeWith over 200 variables going into search algorithms, optimization of code might seem impossible. Luckily, these 200 variables have different weighting, and those that should be at the top of your list to attend to are below.
Title Tag. Every page should have a title tag filled out containing the keyword(s) and/or phrases identified as central to its focus, both for SEO and general readability. In everyday browsing, the title tag is displayed at the top of the browser window for each site you visit. Given the high visibility of the page title to readers, it should be readable to people, not just cryptic keywords lumped together for search engines.
Header Tag. Header tags, of which there are 6—H1, H2, H3, H4, H5 and H6—are HTML formatting tags. The largest of all the H tags, H1 tags display formatted text and are interpreted as placing the greatest emphasis or importance on copy. H1 tags, used sparingly, are often employed to format copy headings or titles, and are ideal to include keyword(s) and/or phrases. Note that H1 tags shouldn't be used excessively, as search engine spiders also account for their abuse.
Meta Description. Often limited to 155 characters, Meta Description tags are used to display snippets summarizing the purpose or content of your web page. It's recommended that web page/site authors carefully craft the content found within this tag to optimally draw visitors to your website. Forgoing to specify content in this tag will result in search engines guessing what to best display.
Keywords/Phrases In Your Copy. The copy of your web page should be relevant and accurate to your subject, but it also should contain your targeted keyword(s) and phrase(s). A word of warning: Don't go too overboard in repeating your keyword(s) and phrase(s) excessively, a practice known as "keyword stuffing," as doing so can negatively impact your standings in search engine results.
Alt Attributes. Alt attributes serve two purposes: 1) provide alternative information to readers about an image in the event it doesn't display; and 2) inform search engines what the image is about. Photographers should consistently populate alt attributes for each image to get the most out of their SEO efforts. Since images can't be read by Google's search engine spiders, directly relaying the content of the images via alt attributes is critical.
Filenames For Images. Descriptive filenames for images and other types of files have an impact on SEO results. An image titled "2013-golden-gate-bridge.jpg" or an HTML page titled "golden-gate-travel-photos.html" will provide more meaningful information to search engines than "2013ggb.jpg" or "ggb.html." If the name of your files share important keywords associated with your copy, you may benefit all the more.
URL File Structure. As with filenames containing descriptive information, subdirectory names and URL structures can help with SEO. A subdirectory titled "travel photography" versus "pages" will help convey greater meaning to readers and search engines alike:
mydomain.com/travel-photography/golden-gate-views.html versus mydomain.com/pages/golden-gate-views.html.