this is html tag next output is in php language 51. Definition of variables in php Variables are "containers" for storing information 51 52. Continued.. As with algebra, PHP variables can be used to hold values (x=5) or expressions (z=x+y). A variable can have a short name (like x and y) or a more descriptive name (age, carname, total_volume). 52 53. A variable starts with the $ sign, followed by the name of the variable A variable name must start with a letter or the underscore character A variable name cannot start with a number A variable name can only contain alpha- numeric characters and underscores (A- z, 0-9, and _ ) Variable names are case sensitive ($y and $Y are two different variables) 53 Rules for PHP variables: 54. Creating(Declaring) PHP Variables: PHP has no command for declaring a variable. A variable is created the moment you first assign a value to it: Example 54 55. PHP is a Loosely Type Language Example In the example above, notice that we did not have to tell PHP which data type the variable is. PHP automatically converts the variable to the correct data type, depending on its value. 55 56. PHP Variables Scope In PHP, variables can be declared anywhere in the script. The scope of a variable is the part of the script where the variable can be referenced/used. PHP has three different variable scopes: local global static 56 57. Local and Global Scope A variable declared outside a function has a GLOBAL SCOPE and can only be accessed outside a function. A variable declared within a function has a LOCAL SCOPE and can only be accessed within that function. 57 58. PHP String 58 59. Strings in PHP A string is a sequence of characters, like "Hello world!". The PHP strlen() function The strlen() function returns the length of a string, in characters. The example below returns the length of the string "Hello world!": strlen() is often used in loops or other functions, when it is important to know when a string ends. Example 59 60. PHP strpos() function The strpos() function is used to search for a specified character or text within a string. If a match is found, it will return the character position of the first match. If no match is found, it will return FALSE. The example below searches for the text "world" in the string "Hello world!": Example 60 61. strcmp() Function The strcmp() function compares two strings. Note: The strcmp() function is binary-safe and case-sensitive. Example Compare two strings (case-sensitive): Syntax: strcmp(string1,string2) 61 62. Example 2: 62 63. More String Functions: 63 64. server-side page using php strings and variables