Free Online Random Number Generator
Generate multiple, unique, decimal, negative, large, unique and cryptographic random numbers with this online random number generator. This random number generator has many useful features:

Large numbers: Generate very big random numbers  up to 100 negative digits and 100 positive digits (that's 10^10 to 10^10). It should be a huge enough range for pretty much anything imaginable.

Multiple numbers: Generate multiple random numbers at the same time  up to 50,000. That should be enough numbers to hand one out to every individual at a typical sports stadium for example, and that's just clicking the generate button once.

Decimal places: Generate random numbers with decimal places  up to 53 decimal places per number. This is a powerful feature, just select the number of decimals you want to let the random number generator to include up to, 0 is the default. You could produce numbers between 0.5 and 1.5 for example.

Negative numbers: Generate negative random numbers with this app. For example you might set a range of 100 to +100.

Unique numbers:Generate online unique numbers and exclude duplicates with this random number generator. This means if a number has already been picked randomly, it will not be picked and displayed again. This can be useful if you want to randomly pick the order of a specific set. It can also be useful to make sure that only one prize is given out per person when picking names in a raffle, for example

Sort the results: Sort the generated random numbers from highest to lowest (descending), lowest to highest(ascending), or leave them in the order they are selected (default). Sorting the numbers generated can be very useful for when you go to make use of the numbers that are created.

Format the results: Format the results of the randomly generated numbers into useful formats; separate numbers with spaces, new lines, commas, commas and spaces, commas and new lines.

Cryptographic random: Generate cryptographically strong random numbers with this random number generator. It uses OpenSSL's
openssl_random_pseudo_bytes in the generation algorithms. This means the numbers produced are based on the same engine and algorithms that produce random numbers for cryptographic purposes (encryption, decryption).
More about Random Number Generation
Ultimately random numbers can be very useful for a huge variety of purposes, whether it's educational, research, entertainment, financial, raffle draws, lottery picks, etc. The need for a random number generator that can be customized to your many needs is important. If you want to use the random number generator to simulate many throws of a dice for example, you can do it just by setting the numbers to between 1 and 6. Or maybe you want to simulate a lottery pick  just generate 7 random numbers between 1 and 49 for example.
Cryptographic Random Number Generation
Cryptography is important for financial institutions, order processing, online security, government, etc. One potential drawback to using cryptographic random algorithms is the number generation may be slower when generating large quantities of numbers compared to the simpler pseudo random option. Pseudo random number engines on the other hand generate random numbers based off of algorithms that technically meet the definition of random, but use definitive algorithms. These would not be ideal for cryptographic purposes, but for most casual purposes pseudo random numbers are secure enough.
What about true randomness you may ask? Well true random numbers are themselves theoretical in nature. All random numbers generated by computers require a certain "seed" value that is put into a complex algorithm that randomizes that value. The more random the seed value the better. However, even the universe has uniformity. Radiation and atoms may seem random in nature, but then why does the earth hold together? Or our bodies don't explode? Believers of true random numbers are therefore proponents of the fallible Chaos Theory. Or something like that.