Hii,
I want to know if the flashcard help kids to learn how to read or only memorized the words??
Both, depending on your definition. 
This is part of the ‘whole words vs phonics’ debate, and there have been many discussions on this on this forum.
Start by reading this article:
http://www.brillbaby.com/teach-baby/reading-whole-language-phonics.php
hi
i tried to depend on the powerpoint only but my 2 year s old daughter cant memorize the word unless i write it on cards!!!
that is funny. My son also learned first the words I would write on paper, but now he learns both, and even recognizes them on packages, or things that are printed… However it is easier to make your child read 10 times a day the same word on the coputer, than to make them pay attention 3 times a day to a paper flashcard.
I think that adults and babies learn differently and therefore babies are frequently misunderstood. Adults learn from the top down; by this I mean that we have to get the big picture or the concept behind something before we can process the details. Babies learn from the bottom up; they gather a whole bunch of details then eventually link them together to grasp the conceptual side. So they are memorizing words but when they get enough pieces together they will see the big picture.
Hi from what I have heard from friends using flash cards, is that babies figure out phonics themselves, they may initially learn the words from memory but then will read out a word they havent seen before. I love using flash cards with my baby as I think she gets a lot out of it. I havent tested her but when I show her the flash cards she concentrates on them intently and only gets upset when I take them away.