SHA-256 processes input data using rounds, which are a series of mathematical operations. Each round includes steps such as preprocessing the data, message expanding, and message compressing. The SHA-256 algorithm is primarily composed of the following steps:

• Preparation of data:
  After adding one bit, the length of the message is multiplied by 512.

• Message Expansion:
  The 512-bit input is divided into 16 words of 32 bits using a series of logical operations. The words are expanded to 64 32-bits words.

• Message Compression:
  After the expansion of the message block, it is divided into 64 rounds. Each round consists of:

• Find the round constant:
  Each round generates a 32-bit constant depending on the position of the round in the order.

• When to send messages:
  A 64-entry schedule is created based on the rounding constant, the message block of 64 words and the message block.

• Updating Working variables:
  To update the eight 32-bit working variables that are used as intermediate values in the hashing procedure, a series of logical calculations and the message schedule is used.

• Calculate the hash value:
  The 256-bit value is created by adding the results of all 64 working values.