Server uptime is the percentage of time your site is viewable
throughout the whole month. Most of hosting companies guaranteed
99%, 99.99% or 99.98% server uptime. If any hosting company
offers 99% uptime your site will be down for 4 days in a year
and this is not good. Because if you are running e-commerce
related site, and it will cost you more even if it down for
half n hour.
So, we highly recommend you to choose a web hosting company
that offer 99.99995% uptime in cheap rate. Some company offer
bulk disk space and bandwidth and features but you must looking
for server uptime because it will cost you high.