Let me explain it through real life example because these concepts sometime seem little bit tricky to understand Lets say there is  box Of Money laying on the table And there is list Posted on the Wall in a Classroom now two students of the class room Go to the box  One Student is Named Ahmed And Second is named as Tanveer  lets say tanveer Put 5$ into the box and Ahmed took 5$ from the box and they Write it on the list  Whole class is seeing this transaction So there is no room  for Cheating 

  1) CONNECTING WITH CRYPTO TRANSACTIONS?

If Ahmed Sent 0.5btc to Tanveer  Then the Validators Will check if Tanveer Really have 0.5btc in his wallet if yes they proceed then they check Wether he signed From his Private keys if yes then they proceed  Then they Check wether Ahmed Now has more 0.5btc if yes transaction is done and Validated it is now in the waiting and its sometime to happen  Whole Network or Nodes of Computer(Classroom) now agrees on the transaction and a block is  Closed And new fresh block is created making previous Block information imteprable and Secure

Let me explain it through real life example because these concepts sometime seem little bit tricky to understand Lets say there is  box Of Money laying on the table And there is list Posted on the Wall in a Classroom now two students of the class room Go to the box  One Student is Named Ahmed And Second is named as Tanveer  lets say tanveer Put 5$ into the box and Ahmed took 5$ from the box and they Write it on the list  Whole class is seeing this transaction So there is no room  for Cheating 

  1) CONNECTING WITH CRYPTO TRANSACTIONS?

If Ahmed Sent 0.5btc to Tanveer  Then the Validators Will check if Tanveer Really have 0.5btc in his wallet if yes they proceed then they check Wether he signed From his Private keys if yes then they proceed  Then they Check wether Ahmed Now has more 0.5btc if yes transaction is done and Validated it is now in the waiting and its sometime to happen  Whole Network or Nodes of Computer(Classroom) now agrees on the transaction and a block is  Closed And new fresh block is created making previous Block information imteprable and Secure