Why are people recommending Chromebooks? Did anyone read the OP? He goes on to say he does not know anything about Chromebooks but he needs a computer with 4 to 8 GB or RAM and a 1 TB HDD. Chromebooks only come with 2 GB of RAM and a 16 SSD with 100 GB of google drive.
Not to mention if you plan on utilizing 4 to 8 GB of RAM the CPU's in the Chromebooks wouldn't support enough task at one time to fill up that much
RAM.
So the answer is simple, get a PC.
EDIT: To answer you OP and make it simple Chromebooks don't work if you need to work with any form of tools. Macbooks are nice feeling hardware however a rip off and price gouge. Apple is still selling a notebook with a 3rd Gen i5, 4 GB of RAM, 500 5400RPM HDD, Intel HD 4000 graphics and 720p display for $1,200. The notebook listed in my specs gets the same battery, far better performance with a 1080p display for $700.
So just go standard Windows PC, far better hardware for the price. Not to mention unless we are comparing Bash and Powershell when looking at just standard use of the desktop Windows 8.1 feels far more responsive and if you ever want to venture down the Unix road you can install Ubuntu or anyone of them and get faster hardware with the power of Unix.
Now before those of you who argue OS X superior security then read...
Why worry about viruses when that can just set your Mac on fire!
https://www.networkworld.com/news/2014/022614-rsa-apple-attack-279212.html
Apple needs to patch! Security flaws!
http://www.zdnet.com/major-apple-security-flaw-patch-issued-users-open-to-mitm-attacks-7000026624/
Those who like to argue security it is not OS X is better then Windows or the other way around. Instead I would argue the difference between open source development and proprietary development. They are finding flaws in OS X and I could provide more links then this but those prove the case. OS X is about 7% market share and they find plenty of security problems which is scary if they had 90% market share and was under the scope far more by hackers. Those who recommend OS X based on security should educate yourself and if you want a truly secure solution open source operating systems are far superior.