Can Anyone Explain The Conversion Of Binary Number System Into Decimal Number System?

Converting a binary number into a decimal number is very simple process.
Let's suppose we have a binary number 1000.
To convert this number in to decimal separate each digit and multiply them with 2 and adding them with each other. Then give power to each 2 starting from right and giving the right most power to 0. Then the above figure will come as:

1 x 2 + 0 x 2 + 0 x 2 + 0 x 2
Then giving power.
x 2^3 + 0 x 2^2 + 0 x 2^1 + 0 x 2^0
8 + 0 + 0 + 0 = 8
The 1000 in binary will 8 in decimal.
You can have an alternate method.
Start from right, multiply the first digit by 1 then second by 2 third by 4 fourth by 8 fifth by 16 sixth by 32 and so on. Just making it double. Let's we have 1010100

1 x 64 + 0 x 32 + 1 x 16 + 0 x8 + 1 x 4 + 0 x 2 + 0 x 1
64 + 0 + 16 + 0 + 4 + 0 + 0 = 84
After some practice this will clear all problems. Start practising with smaller values and then by using the higher values.