Compared with HTML4, Upload Components have a more user-friendly interface and support a wider range of features.
[1][2] With HTML forms a user's files can be uploaded by employing tag with different attributes.
For upload functionality, new HTML5 APIs[4] offer a wide variety of new features, including access to the client's file system and dynamic request-generating and processing of images.
The situation becomes worse if we remember that large numbers of users still use Windows XP (28%)[5] and obsolete Internet Explorer versions (11%).
[6] Upload components can be developed on the basis of various technologies aimed at extending browser functionality.
Depending on the technology and its features, upload components can support more or less functionality, be more or less configurable, and be easier to use.
Java applets are signed with security certificates to become trusted software, which allows automatic redistribution from a web site and installation on client computers.
Another type of upload components is Silverlight which is a Microsoft technology requiring a browser plug-in to be installed.
The best coverage of HTML5 features is provided by the latest version of Chrome, Firefox, Safari and Opera.