A slow Internet connection could be caused by any number of reasons.
 Below is a short list of some of the more common reasons your Internet connection may be slow:-
Slow Internet connection:
If you're using a dial-up connection or a modem this will be much slower than any type of broadband connection or a connection you may be used to at work or school.
If you're using a modem no mater how fast your computer is the speed of the Internet will remain the same or very close and can cause some users to believe their computer is slow.
If broadband is available in your area and you would like a much more enjoyable experience on the Internet we highly recommend getting it.
Type of site or download:
Depending on the type of site you're visiting or the download you're receiving your Internet connection may appear to be slow.
A site such as Computer Hope, which is 90% composed of text documents will load much faster than a website such as YouTube, which is composed of movie files.
Downloading while browsing:
If you're doing more than one thing while on the Internet you'll notice browsing the Internet is slower.
For example, if you or your kids are downloading a game, movie, music, or other type of file. While the computer is getting that data all other browsing will be slower.
Time of day or day:
The time of day or what day it is can often affect the overall speed of the Internet as well as your individual connection.
When more people are online servers and Internet connections can become overloaded and cause delays in the response.
 In addition users who are using broadband cable to connect to the Internet share an individual cable with neighbors who are also subscribed.
If all your neighbors are on at the same time you will notice a decrease in your speed.
Times when people are at home, e.g. off from work or school (after 3PM) or weekends (Saturday / Sunday) are often slow times.
Sites like Internet Traffic Report actually report the flow of data around the world. This type of site can give you a rough idea of busy times.
Server or website location:
The location of the web page you're visiting can also determine the speed of the Internet.
If you're accessing a web page that is n a different part of the world it will be much slower than a page that is hosted closer to you.
Visitors on site:
A server or web site can often only handle so many people at once.
If hundreds, thousands, or millions of people are trying to visit the site at once that page will be much slower and in some cases pages may not even respond.
Network or site maintenance:
If your Internet service provider or the host of the web site is performing maintenance on their network, computers, or network equipment this can cause speed related issues.
Other major event:
If a major event is occurring around the world, it may cause speed related issues.
For example, during the tragic events of September 11, 2001, where terrorists attacked United States many of the news sites were so overwhelmed with visitors that they would either take several minutes to load or not load at all