What does meant by the block of blockchain, for what purpose they are ?

[marleybobthedog]

I new member of bitcoin network and which surfing the net about bitcoin i had found block term in many sites, what does the block mean. Please help me understand block with real life or any sutable example.

[hajimasan]

The block chain is a shared public ledger on which the
entire Bitcoin network relies. All confirmed transactions
are included in the block chain. This way, Bitcoin wallets
can calculate their spendable balance and new
transactions can be verified to be spending bitcoins that
are actually owned by the spender.

[franky1]

in short
a block is just a clump of data. it can be anything
a blockchain group of blocks where the identifier is made by including the identifier of the last block, which includes the identifier of the previous block.

meaning block 400k's single hash represents the combined data and collection of 400k blocks.. if 2 people recognise that single hasn they both know they have all the exact same data contained in 400k blocks and it all matches

long version in laymens

block is just a block(clump/batch) of data.. which can be anything. a list of favourite songs. book where each block is a chapter of text.. or a batch of transactions.

this block of data then has a hash to identify it.
this way you dont need to send the entire data to someone else. you can just send the hash and if they say they have the same hash, you both know you both have the same block of data and the text is exactly the same. this is because change any of the data changes the hash..
eg - very laymans
data: Joyful Artistic Nice Energetic, hashes to JANE
no need to say do you have data: Joyful Artistic Nice Energetic...... but instead do you have: JANE

next lets describe the chain.
by including the hash of the previous block with the data of the next block.. the new hash not only can be used to say you have the second blockdata but also the first. and both are complete


EG - very laymens understanding
imagine you had 4 people..
now imagine their personality was a long story(i just got lazy and put in 4 words for dummy example)

person 1 is named by hashing their life story (joyful artistic nice energetic, hashes to JANE)
person 2 is named by hashing their life story (joyful artistic caring kind, hashes to JACK)
person 3 is named by hashing their life story (brave intelligent loving lazy, hashes to BILL)
person 4 is named by hashing their life story (joyful obedient honourable nice, hashes to JOHN)

blocks work because instead of asking others do you have data:"joyful artistic caring kind"... you simply ask do you have JACK

and chains add another layer

first we see JANE you tell the other person i have JANE.. they then know you only have one person
next we create JACK.. we combine the hashes.. to get a new hash JJAANCEK you tell the other person i have JJAANCEK.. they then instantly know you have 2 people and their data are complete and correct

now imagine time went on, you dont have to ask for JANE or JACK or even JJAANCEK .. if you now have 4 people you can just ask for JJBJAAIONCLHEKLN and the other person recognises your now at person 4 and all the data is correct for all 4 people without you ever needing to tell them at some point you got person 3 by transmitting any information about person 3 prior.

so say you had 400,000 blocks.. you just need to send ONE hash, that is a chain of all 400,000 blocks that reveals that:
1. you have block 400k
2. you have all other 399,999 blocks too
3. that all 400,000 blocks are complete and the data is valid

bitcoin vs blockchain:
bitcoin itself has atleast 8 other security features ontop of blockchain.. but dont confuse bitcoin and blockchain.
bitcoin uses blockchains and another 8+ things.. but blockchains are not bitcoin..

the data in the blocks dont need to be financial data, the hashes can be made using any algo (doesnt have to be sha256)
the data doesnt even need to be double secured (POW or POS), hense why i didnt mention that part.

its just a way of batching ANY data into blocks/clumps/groups (it all means the same thing "blocks") and then chaining each block together to speed up the checking time.

anything else ontop of what i have said is outside of the "blockchain" descriptor, but can be added to give extra security features to do certain tasks(as i said it takes atleast 8 things to make bitcoin what it is, 7 things to make a POS coin what it is) but they all fall under the umbrella of blockchain because they all use a blockchain as PART of their feature

[~Bitcoin~]

Block mean batch of transaction which were verified by the miners and confirmed. Miners can set their own recommended fee for transaction so that any transaction that have enough fee allocated will only be included in the block they will mine. Each block have their unique hash as well as id so that it can be checked later on anytime in future, which shows all the transaction that were included and confirmed within that block in past.