This is fiercely dependent on your filesystem, but since the de facto standard filesystem for now is ext4, the typical maximum is 255 characters. It's not going to be practical to go over every filesystem Linux supports, so I'll just say read the manual.
Starting from /home, the path may include up to 4,091 additional characters (that is, Linux supports 4096 characters for the path, with up to 256 characters per file or directory name). This is a limitation of the kernel, and not of the file system. It is technically possible to modify the Linux kernel to support even longer file and path names if a user needed to do so.
It means that the file or directory is used for application settings.
4096
The kernel image is the file in /boot that has a name like "vmlinuz" in it.
The first file system Linux supported was the MINIX file system.
The /, or root directory.
./ <program file name>
/etc/passwd
There is no set file manager in linux. Examples of Linux file managers include but: Nautilus (GNOME) Thunar (XFCE) Dolphin (KDE)
/etc/ncsd.conf
The Linux VFS (Virtual File System) may be thought of as a sort of interface between the Linux kernel and the mounted file systems. There can be many different file system types mounted simultaneously and VFS allows the Linux kernel to see and address them all in a similar way. This provides Linux with a great deal of flexibility. [JMH]
Super block is supposed to be the first sector of any file system that can be mounted on Linux operating system. It is supposed to contain information about the entire file system in that partition. It has magic number to specify which file system is used in that partition and other parameters to help read/write to that file system.