Visual Aids
The need for visual assistance can range from being completely blind, low vision or to colour blindness. Many OSs (Operating Systems) have been designed to aid users who are visually impaired through tools such as a text-reader function that reads out loud what is being displayed on a screen.
Not only this, but the way that some programs' code is initially wrote can be helpful in this manner. Alternative text (or 'Alt' text) are words or phrases that can be written within HTML (Hypertext Markup Language) documents which informs the user of the contents of what they are viewing.
Many computers and mobile phones will offer a type of magnifying tool, this is so that the display can be enlarged and easier to read. The visual display of an interface could also be designed with the potential of users with colour blindness. For example, users who cannot visually detect colour should be presented with a colour scheme that clearly distinguishes objects like text apart from the background. Poor use of colour for an interface in general could cause eye strain so this is usually kept in mind for good HCI.
Audio Aids
Such as is for those who are visually impaired, those who find it hard to hear may benefit from HCI which can read text aloud for the user. However, a more beneficial feature for complete deafness is the use of captions and transcripts for medias like videos and audio recordings. This shows the user text of what might be being spoken and also any other audio information like sound effects or types of music.
Physical Aids
HCI software features can improve the accessibility for users with physical disabilities just as much as specialised hardware such as keyboards and mice can. Those without the use of their hands can use voice operated HCI, which means that by speaking basic commands to their phone/computer the software can detect key words from the speech and intentionally carry out said commands. This kind of software has been constantly under development so that it becomes more accurate and able to perform the correct tasks.
For those who can move their hands yet are limited, other features include predictive text, and TAB control. Predictive text will try to guess what word is trying to be typed and if the word is either left incomplete or misspelled it try to replace with what it believes is the intended word. If words are commonly used together, they can also be offered without having to start typing it, if accurate this can greatly limit the number of actions needed to produce text. TAB control works in a similar way as if able to use it means that the user can navigate a web page without having to use a mouse and just need a keyboard.
