Brief History
JavaScript first emerged in 1996
and was a programming language written by Brendan Eich for Netscape.
Initially, it was developed so the code could be embedded in Web pages
so it could process numbers and modify the contents of forms. Over the
years, the use of JavaScript code has increased exponentially and is
now used in a great many ways, including image manipulation and
mouse-over effects etc. Although it is now such a popular programming
language in it’s own right, there are few minor niggles and issues to
be aware of.
Advantages
Speed - because all the code
resides on what is known as the ‘client-side’, response times are fast.
The alternative to client-side is known as ‘server-side’ and this
involves your computer having to wait for a response from a command or
instruction to a computer server somewhere out on the Web.
Simplicity
- JavaScript as a computer language is not too difficult to learn and
there are stacks of resources available on the Internet to help you. It
is also possible to download masses of high quality code example
free-of-charge and this can help you to reduce time demands and also to
assist you in understanding the language dynamics.
Versatility –
Unlike PHP and SSI scripts for example, JavaScript is highly
co-operative with other computer languages and can be used in
conjunction with a great many applications. Another good thing about
JavaScript is that it can be inserted in any web page irrespective of
your chosen extension (e.g .htm, .html & .php etc.).
Load on servers - Because it is client-side, there is no demand placed on the server where the website resides.
Disadvantages
Security
- An important consideration is that because the JavaScript code is
executed on the user's computer, there is a chance of it being
exploited in a malicious way. For this reason, some people cautiously
disable JavaScript from operating on their computer. This is not the
major consideration, but it is worth bearing in mind as you develop Web
applications.
Browser incompatibility - An ongoing problem is
that JavaScript can be interpreted in different ways by the various
browsers. The most important thing is that you verify the operation of
your JavaScript code in the major browsers and do not get too hung up
about the rest.