Efficient only has meaning if you compare it to something else. Like any other operating system it has efficiencies and inefficiencies. It depends on your environment.
vsftpd is an FTP server for unix-like systems that is specially built to be efficient and very secure (very secure FTP daemon).
One of the major advantages of unix based hosting is that unix is free, so the cost is not an issue. Another cost benefit is that several free applications are available for Unix based servers so the money that would have been allotted to this could be utilized elsewhere. Unix is also very efficient because less system resources are required which means less bandwidth and RAM are used. This results in a smoother and faster site. Many languages were developed using Unix as well. This means that there are more applications will be able to run on your site than if you had chosen another platform.
UUCP is the abbriviation of Unix to Unix copy. It is worldwide email system called UUCP or Unix to Unix copy.This email system was developed for the operating system called Unix.
No, but Linux is based on Unix since Linux is a Unix clone.
Unix work is performed by users of the unix system, for application and system programs, or anything that requires a Unix system.
A computer that runs Unix.
Unix commands
A Unix console is a CLI interface through which to control or monitor a Unix computer.
Unix configuration is the process of tailoring a freshly installed version of Unix to your particular environment. Each Unix system may do that differently.
Solaris is a specific version of Unix; the term 'Unix' refers to a classification, and several vendors provide a Unix-like environment. So, in a sense, Unix and Solaris are the same thing.
There is no "default" Unix shell. Different Unix vendors shipped different shells.
Unix was created first. The C programming language was created for Unix.