If elif and else statement

#! /bin/bash

count=10

if [ $count == 10 ]
then
    echo Equal
fi

echo ------------------------------------------------------

string_check=abc

if [ $string_check -eq abc]
then
    echo Equal
fi

echo ------------------------------------------------------

string2=xyz
if [ string2 -nq xyz]
then
    echo Not Equal
else
    echo Equal
fi
echo ------------------------------------------------------

string3=pqr
if [ string3 -eq abc]
then
    echo The value is ABC
elif [ string3 -eq xyz ]
    echo The value is XYZ
else 
    echo The value is $string3
fi

Conditionals let us decide whether to perform an action or not, this decision is taken by evaluating an expression.

Expressions
An expression can be: String comparison, Numeric comparison, File operators and Logical operators and it is represented by [expression]:

String Comparisons:

= compare if two strings are equal
!= compare if two strings are not equal
-n evaluate if string length is greater than zero
-z evaluate if string length is equal to zero

Examples:
[ s1 = s2 ] (true if s1 same as s2, else false)
[ s1 != s2 ] (true if s1 not same as s2, else false)
[ s1 ] (true if s1 is not empty, else false)
[ -n s1 ] (true if s1 has a length greater then 0, else false)
[ -z s2 ] (true if s2 has a length of 0, otherwise false)

Number Comparisons:

-eq compare if two numbers are equal
-ge compare if one number is greater than or equal to a number
-le compare if one number is less than or equal to a number
-ne compare if two numbers are not equal
-gt compare if one number is greater than another number
-lt compare if one number is less than another number

Examples:
[ n1 -eq n2 ] (true if n1 same as n2, else false)
[ n1 -ge n2 ] (true if n1greater then or equal to n2, else false)
[ n1 -le n2 ] (true if n1 less then or equal to n2, else false)
[ n1 -ne n2 ] (true if n1 is not same as n2, else false)
[ n1 -gt n2 ] (true if n1 greater then n2, else false)
[ n1 -lt n2 ] (true if n1 less then n2, else false)