ISP stands for Internet Service Provider. There are many Internet service providers famous for the internet service they provide worldwide.
ISP provides internet access to customers (users and organizations). If you want an internet connection at your home or at your organization then you will need an ISP and a router to connect to the ISP.
Tips on choosing an ISP
Check for equipment
Your computer must have the software installed that is required by your chosen ISP as some of the IPSs require a specific browser as well as a specific router.
Check ISP plans/offers
Check ISP plans and offers and select the plan as per your requirements. While selecting a plan consider how many files transfers, downloads you will need and the speed as well!
If you have a phone connection you can connect to the ISP router/modem.
Internet access can be provided by various broadband technologies such as Mobile or wireless connection, satellite, cable, dial-up etc.
Please check this article to get more information about all the broadband technologies:
If you want to build your own website
If you want to build your own website, choose an ISP that offers web hosting space in the same package.
Here is the example of a good ISP that is providing hosting space as well : Cogent
If you are using the Internet for business purposes then you should get instant technical support to avoid downtime. Also, check if they charge extra for this support.
One more thing you can do to before selecting an ISP is to can take the opinions of other ISP users in your area to get an idea about Internet speed and the service provided by that particular ISP.
All the above points will help you select the correct Internet Service Provider i.e ISP.