How to Convert html to Wordpress

Why should you build your own WordPress Theme?

• .It's an opportunity to learn more about CSS, HTML, and PHP.
• .It's an opportunity to put your expertise with CSS, HTML, and PHP to work.
• .It's creative.

Basic Requirement 

Basic thing are required when developing a wordpress theme or converting html to wordpress

At the very minimum, a WordPress Theme consists of two files.

1) style.css

2) index.php

Typical template files include

1.  comments.php
2. comments-popup.php
3. footer.php
4. header.php
5. sidebar.php

To include the header, use get_header().

To include the sidebar, use get_sidebar().

To include the footer, use get_footer().

To include the search form, use get_search_form().

here is function name include header,footer,sidebar,

Example :    

<?php get_header();?>

<?php get_sidebar(); ?>

<?php get_footer(); ?>

Functions file

A theme can optionally use a functions file, which resides in the theme subdirectory and is named functions.php. This file basically acts like a plugin, and if it is present in the theme you are using, it is automatically loaded during WordPress initialization (both for admin pages and external pages). Suggested uses for this file.

Template Files List
Template Hierarchy for more information.

style.css
The main stylesheet. This must be included with your Theme, and it must contain the information header for your Theme.
Style Guide line
rtl.css
The rtl stylesheet. This will be included automatically if the website's text direction is right-to-left. This can be generated using the RTLer plugin.
index.php
The main template. If your Theme provides its own templates, index.php must be present.
comments.php
The comments template.
front-page.php
The front page template.
home.php
The home page template, which is the front page by default. If you use a static front page this is the template for the page with the latest posts.
single.php
The single post template. Used when a single post is queried. For this and all other query templates, index.php is used if the query template is not present.
single-{post-type}.php
The single post template used when a single post from a custom post type is queried. For example, single-book.php would be used for displaying single posts from the custom post type named "book". index.php is used if the query template for the custom post type is not present.
page.php
The page template. Used when an individual Page is queried.
category.php
The category template. Used when a category is queried.
tag.php
The tag template. Used when a tag is queried.
taxonomy.php
The term template. Used when a term in a custom taxonomy is queried.
author.php
The author template. Used when an author is queried.
date.php
The date/time template. Used when a date or time is queried. Year, month, day, hour, minute, second.
archive.php
The archive template. Used when a category, author, or date is queried. Note that this template will be overridden by category.php, author.php, and date.php for their respective query types.
search.php
The search results template. Used when a search is performed.
attachment.php
Attachment template. Used when viewing a single attachment.
image.php
Image attachment template. Used when viewing a single image attachment. If not present, attachment.php will be used.
404.php
The 404 Not Found template. Used when WordPress cannot find a post or page that matches the query.