Hyper Text Markup Language or HTML is a coding language type understood by coders and web designers. Though HTML is not essential today to design your website as lots of softwares and programs can do the coding work for you as well as content management software (CMS) like WordPress, Joomla etc have made the tough job of designing easy. Though little HTML knowledge might be necessary and we can see such implementation in widgets, header of a blog. Thus you might like to learn HTML and CSS at least a little if you like to make yourself a step advanced.
CSS or Cascading Style Sheets has also made the tough job easy of implementing the same task on each and every page. Once you use a design in a page, it can work in all pages of your site based on your implementation.
If you are new to CSS and want to tweak your website design in your own way, you can try Mozilla Addon Firebug to test out different elements of CSS. Moreover you can test all the elements of your blog with this cool extension without any impact on your site, but make sure to take backup of your CSS file if you are practically implementing it on your site.
Where to Learn HTML and CSS Online
EBooks & E-Courses
E-Books & E-Courses can be a good way to start if you have patience and concentration to learn your own. Though not all eBooks are well-written and easily understandable, so you need to be selective while choosing eBook. You can learn HTML and CSS free downloading following free EBooks.
Most people prefer videos over reading. This way they can visualize the whole process and can remember more easily. It is also useful for beginners to learn things faster. Videos are also faster to learn and hassle-less. You can learn HTML and CSS from following video courses available online.
Membership sites offer premium courses which can be avail spending few bucks online. Since they are professional courses, you can learn HTML and CSS fast and more professionally if you are willing to invest. You can find paid few membership options here-
If above courses do not satisfy you, learn HTML and CSS free online from various other sources too. Give a Google search and check more resources online including PDF, eBooks and Videos.