Well yes, I would just like to give some more details for those who find the answer a bit complicated or those just migrating from windows to Linux platform....
In Unix/Linux, there are 2 kinds of paths:
1. Absolute Path
2. Relative Path
1. Absolute Path -> This is the complete path which needs to be given in order to execute a particular file in relation to the root directory(/).
for example, to run the command 'clear' which is located in /usr/bin, we can specify the complete path to the command...i.e
2. Relative Path -> A Relative path does not be start with a '/'. It specifies the path in relation to the 'current directory'.
There are 2 shortcuts that the system creates for every directory file created namely (.) and (..) where (.) stands for the current directory and (..) means the parent directory (one-level up).
So, suppose, if our present working directory is /usr/local/bin and we want to execute the clear command, located in /usr/bin then the relative path will be as follows:
Thus, ./filename infoms the shell that the file <filename> is an executable located in the current directory.
[user@localhost bin]$ ./configure [. stands for /usr/bin]