Like Internet Download Manager for windows,Is there any software to download all files like videos,audios,softwares and all other files in Ubuntu 11.10?
Here is a quick solution. You do not even need a software to download videos from web.
All you have to do is run following commands after the video has been completely loaded on browser.
Replace PID and FD with their corresponding value from the output obtained from the first command.
Consider following example.
If you just need to download videos (as the question title suggests), Video DownloadHelper it's a nice add-on for Firefox that works fine.
Videodownload helper extention for Firefox works fine for videos. DownloadthemAll extention for other files (download acceleration, filter rules to download multiple files at one go, etc.)
Even in IDM (or Orbit or any other downloader), you need a link or the URL, which locates the resource and can be used to download the file from the remote server.
If you have a link, you need a download manager (like how you used IDM).
If your query is limited to downloading videos from the Web, you might want to get their links and use a download manager still. If not, you might want to go over the extensions of your browser.
Download Manager for Ubuntu
I personally recommend SteadyFlow, but you're recommended to go through all of them and choose for youeself. For doing that, open Software Centre, and search for "downloader". SteadyFlow is the most rated as of now.
Most popular browsers have extensions that facilitate downloading videos from online streaming websites. Search for them. But in the end, they too just grab the link and download via your browser's download manager (which is pretty slower than a standalone download manager).
For example, if you have Firefox, you can press Shift+Ctrl+A to open the "Add-Ons". Here, you can search for extensions with queries related to "download videos". I personally use FlashGot, which is used to get the link of any media: video, image, music, etc.
Alternatively, there exist many online tools for that purpose. You can run a Google search with "download videos online" for the latest results. You can use those services to download videos from particular websites.