Why does wget only download the index.html for some websites?

Wget is also able to download an entire website. But because this can put a heavy load upon the server, wget will obey the robots.txt file.

 wget -r -p http://www.example.com

The -p parameter tells wget to include all files, including images. This will mean that all of the HTML files will look how they should do.

So what if you don't want wget to obey by the robots.txt file? You can simply add -e robots=off to the command like this:

 wget -r -p -e robots=off http://www.example.com

As many sites will not let you download the entire site, they will check your browsers identity. To get around this, use -U mozilla as I explained above.

 wget -r -p -e robots=off -U mozilla http://www.example.com

A lot of the website owners will not like the fact that you are downloading their entire site. If the server sees that you are downloading a large amount of files, it may automatically add you to it's black list. The way around this is to wait a few seconds after every download. The way to do this using wget is by including --wait=X (where X is the amount of seconds.)

you can also use the parameter: --random-wait to let wget chose a random number of seconds to wait. To include this into the command:

wget --random-wait -r -p -e robots=off -U mozilla http://www.example.com

Firstly, to clarify the question, the aim is to download index.html plus all the requisite parts of that page (images, etc). The -p option is equivalent to --page-requisites.

The reason the page requisites are not always downloaded is that they are often hosted on a different domain from the original page (a CDN, for example). By default, wget refuses to visit other hosts, so you need to enable host spanning with the --span-hosts option.

wget --page-requisites --span-hosts 'http://www.amazon.com/'

If you need to be able to load index.html and have all the page requisites load from the local version, you'll need to add the --convert-links option, so that URLs in img src attributes (for example) are rewritten to relative URLs pointing to the local versions.

Optionally, you might also want to save all the files under a single "host" directory by adding the --no-host-directories option, or save all the files in a single, flat directory by adding the --no-directories option.

Using --no-directories will result in lots of files being downloaded to the current directory, so you probably want to specify a folder name for the output files, using --directory-prefix.

wget --page-requisites --span-hosts --convert-links --no-directories --directory-prefix=output 'http://www.amazon.com/'