Question:What is x+ mode in fopen() used for? 

Read/Write. Creates a new file. Returns FALSE and an error if file already exists

Question:How many ways you can read a file?
     

We can read a file by using the following file modes :
           R, r+, w+, a+.

Question:How many ways you can read a file?

 

We can read a file using the following methods and  modes:

Methods: file(), file_get_contents(), fgetcsv(), fgets(), fgetss(), fgetc(), fread(), readfile(), fscanf().

Modes: R, r+, w+, a+, x+.

Question:How many ways you can write into a file?

 

We can write a file using the following method and modes:

Method: fwrite() with fopen() and write mode, file_put_contents(),fputcsv(),fputs(),fputc().

Modes: r+, W, w+,A,a+,X,x+.

Question:What are the technical difference between echo() and print() function? 

The echo() function is a bit faster because it returns nothing, whereas print() will return 1 if the statement is successfully output.

Question:What is datatype? 

A datatype is the generic name assigned to any data sharing a common set of characteristices.  Common data types include Boolean, integer, float, string, and array.