Traditional software was purchased and then installed on a computer or server (for use by a number of computers within an organisation). Computers are sometimes replaced and new software is purchased; they come with preloaded software and an operating system (e.g. windows).
When a new laptop is purchased, it also has pre-loaded software, after a month the user is asked for $100's to continue to use the programs. An 'office' licence for 1 computer 1 user can cost $350. It cannot be used on another computer, and it may only be used infrequently.
Software as a Service (SaaS) does not require the user to pay 'up front', they can use the program and pay only in relation to its use (on demand).
This is ideal for a company that previously had to buy a number of licenses for both desktops and laptops (so an individual could work outside the office). Many people on the move now have tablets and smartphones. If the recruitment software is on their office computer, they cannot use it when 'out and about'. In contrast to this, web enabled SaaS can be used on any internet device, android tablet or even a Smart or Google TV.

How does SaaS work
In the past, a software program was loaded onto an individual computer, using the hard drive (which sometimes became full). There are a number of drawbacks, sometimes the program became dated, sometimes the hard drive failed or became corrupted, sometimes the user purchased a new computer.
As an alternative to loading programs on each computer with an associated licence, companies stored the software on a central computer (a server), but then had to have an IT department to keep the network servers working and backed up.
Software as a Service removes this expense by having the software 'on a cloud'; any user can access it and can use inexpensive devices. Software on a cloud can be compared to a computer hard drive being 'somewhere on the internet', and the rest of the computer (e.g. keyboard and display) linked to it over the internet. Another comparison could be with older SatNavs which had their own map installed; this could become out of date if not updated. If using google maps on a computer or android device, it is always accurate as it is effectively on 'a cloud'.

Advantages of SaaS for Online Recruitment Software
The recruitment professional can access the software anywhere and at anytime, they do not need to be at work, they don't have to have a wireless laptop, they can use any internet device, android device, tablet etc. Tablets are less expensive as they do not have pre-installed software (e.g windows, office etc.), the price reflects the manufacturing cost. India has just introduced a $30 (Rs 1500) tablet, these are able to run Software as a Service easily and quickly.

Because SaaS software can be easily used with tablets etc., whilst 'traditional software' is only used on computers, SaaS software 'is the future' and is a market that is growing. Software as a Service online recruitment software can target candidates and parse CVs. It can be updated without the user having to see a message 'an update is available, do you want to load it now - your computer will re-start in 5 mins'. It is able to grow with the company; as it is on demand (pay as you go), costs are less than conventional software.

The author (Dave Hudson) is a former University IT lecturer and has written numerous articles on software; Drupal, android development, Google TV development etc. This is a third article on Cloud and <a online recruitment software.