DHTML Object Model

Every element within the DOM is made up of its own set of properties, methods and events, the object model will focus on collections of all elements and the hierarchy of groupings that each element fall into. The major collections or components of the DOM are the all collection and the children collection.  These collections will give the document a structured arrangement and each element will be influenced by these collections depending on where they sit within the document.

1.       The all collection is able to find all elements within a document that are beneath it within the hierarchy,  whereas the getElementById() will only find an individual element by its ID within the document.

2.       An onkeypress requires and press and release to start and end the event, if the key is held down the event will be launched multiple times. The onkeydown is a single event, even if the key is held down the event will only be activated once.

3.       Any event that doesn’t have a event handler assigned to it used to be removed completely, but event bubbling will pass these unhandled events to the parent element, it will pass the event up the hierarchy until it is handled or until it reaches the topmost object.

4.       To cancel a event the window.event.cancelBubble property must be set to true, unless this is set the events will keep bubbling up the hierarchy until it has been handled by all parent elements within the event even if the event has already been handled.

Twitter

Twitter is a shortened version of a blog. Twitter will allow only 140 characters in each message posted, similar to a mobile phone text message. Twitter is used to keep friends and family informed on events that happen in your day and also allow you to read massages posted by your friends on their daily events.

 

Twitter uses followers and following options to show which twitter accounts you read and the users who read your posts. Followers are the friends in which have added you to their account so they can read and reply to your posts, and following are accounts which you have added to your own account to keep up to date with.

 

Twitter is useful because unlike normal blog sites where it could be weeks or months between posts, twitter is utilised as an all day every day social networking site similar to how we would use our mobile phones to organise social gatherings, keeping in touch, etc. Twitter isn’t just centralised to your pc, it can be linked to your mobile phone so you can keep update and in touch with the people who matter most to you when your on the go.