We often hear kids chanting "The Alphabet Song" - ABCDEFG-HIJKLOMNOP-QRSTUVWXYZ! Have you noticed the sequence of alphabets while they sing? By-hearting isn't the right way to teach beginners, English. They need to identify and recognize the sounds of each letter as well as a blend they form in a word.
Phonics is a systematic way of teaching beginners to identify letters sound and grouped letters sound and identify letters while they write words.
Phonics is an approach associated with the teaching of reading and writing the words with the help of the phonemes (sounds of letters) with the particular graphemes(letters), both in isolation and combination of letters.