Introduction - If you have any usage issues, please Google them yourself
SHA1 generates a 160 bit message digest. The algorithm has been developed and improved by encryption experts for many years, and has been widely used. The idea of the algorithm is to receive a plaintext, then in an irreversible manner to convert it into a (usually smaller) ciphertext, also can be simply understood as taking a string of input code (called pre mapping or information), and put them into a short, fixed length digit output sequence the hash value (also known as the information or message authentication code) process