Question: What's the difference between "transfer" and "bandwidth" (or mbps) when comparing hosting plans?

Answer: Both terms relate to the amount of data you can transfer between your server and the people who visitor your site on our server.  Both are sometimes used interchangably, but they are actually 2 different ways of buying that same resource. 

Transfer refers to the total number of BYTES of data transferred in a given period of time.  3Essentials hosting plans include X amount of bytes of transfer for a month... for instance 100GB (roughly 1 billion bytes).

Bandwidth refers to the amount of bytes transferrable in a period of time, for instance 1Mbps, means 1 million bytes per second.  Now, this term "bandwidth" can be used to refer to describe CAPACITY or AVERAGE UTILIZATION:

• THROUGHPUT CAPACITY:  For example, on our dedicated server plans, we typically connect your server to a 100Mbps connection, which is then connected to a gigabit ethernet backbone.  So the "pipe" through  which data flows to your server, is maximum throughput capacity of that 100Mbps connection to your server. 
• AVERAGE UTILIZATION: to reflect average usage...  for instance, let's say that same dedicated server hosts a small website, which doesn't get much traffic... it may only actually utilize .5Mbps on average through the month.   At the end of the month, we average your utilization, if it's 1Mbps or below, you're fine.  If it's over 1Mbps, say 1.5Mbps, then there is a charge for the additional usage. 

Think of your residential water service as a perfect example of a similar concept...

• The city might be able to deliver you 100 gallons per minute, that's your THROUGHPUT CAPACITY of your BANDWIDTH.  We'll say 100GPM for shorthand.  That's the fastest RATE at which you could get water coming into your house if you opened every faucet in your home wide open.
• At the end of the month, you used 1000 gallons.  That was your TRANSFER... the total number of gallons TRANSFERRED to your house during that month.
• So you used 1000 gallons in a month... the average usage in "gallons per minute" would be 1000 gallons divided the number of minutes in a month.  This actually comes out to be= .023 GPM.  So this is your AVERAGE UTILIZATION of your BANDWIDTH. 
• You can see there that even though BANDWIDTH can be used to mean both CAPACITY (100 GPM) and AVERAGE UTILIZATION (.023 GPM), there can be quite a difference between the two.  
• Now the question... how do you want to pay for your water?  total gallons usage?  or average utilization, Gallons Per Minute?  Well... it depends on how you use your water, doesn't it? 

When you're purchasing a hosting plan, you'll find you may have some options as to whether you purchase TRANSFER or BANDWIDTH with your hosting.  For 3Essentials, you'll find the following:

• On our SHARED HOSTING plans, we only offer the TRANSFER option... the total number of bytes transferred per month.  Then you say "how much do I need?"... well the simple rule is, if you have to ask that question, then you only need the smallest amount available in our plans.  Seriously... if your site has heavy transfer needs, you'd know it by now, and you'd know exactly how much you need!  If you are coming from another hosting provider, you should actually be able to get exact statistics from your previous hosting provider that would tell you exactly how much monthly data transfer you've used historically.  Our shared hosting plans are LOADED with transfer... and you can upgrade plans to get more transfer at any time without a charge for upgrading plans.  So look at your OTHER needs for plans (like # of databases, etc), and don't worry much about transfer.   Our control panel will provide you with a daily report of your transfer usage.
• On our DEDICATED SERVER hosting, you have the option of purchasing this resource by either TRANSFER (total number of bytes transferred in a month) or by BANDWIDTH (Mbps)/ average utilization.  Which you chose will depend on you, your site and your preferences.  It's a little like  the myriad of cell phone plans... it all depends on your calling patterns.  The Bandwidth options are available at 1Mbps and go up to whatever you need.  This doesn't mean your maximum throughput capacity is 1Mbps, it means you're paying to use up to an average of 1Mbps with no additional charges.  We do this averaging based on the 95th percentile method.  We sample your usage and discard the highest 5% (this helps you with any spikes you had). 
• Again, if you're just starting out, and you don't know your network needs, don't worry too much about it, pick one or the other, and pick a minimal option.  We can always adjust your bandwidth pricing as your demands grow.