Fast Copy is an advanced copying tool which is both faster and more custamizable then windows built in copy.
It does so by not using MFC.
It uses multiple threads ( its like splitting a task in to many sub task and then doing concurrently) thus is faster then in buit tool, but at the same time consumes more CPU.However CPU consumption can be customized by using speed control option at expense of speed.It supports "Auto slow" option to slow down speed as well as resource consumption if Fast copy is not in foregund or mouse movement is detected.
It provide bunch of custàmizations like time and date based operations, option to synchronize, ignore errors, CRC check.
Although it comes with lot of cus5omizatioñ windows 10 built in copy is not far behind in speed and is rather hassle free then Fast çopy viz. no setup required and plays on safe side while cutting i.e. files are not lost in any circumstance while Fast Copy sometimes gets anxious and led to file corruption. Also FastCopy has to deal with file permission granting problem especially while drag and drop functionallity is used.
To conclude if your PC runs on windows 7 or older or the extra functionallity provided are of too frequent use for you you should go for Fast Copy other wise it can be avoided