:salam:
^ If you are reading in Hafs an Aasim recitation (which is the recitation most Muslims use), then in Surah al Faatihah, you read Maalik, and not Malik. However, if you are reading in Warsh recitation, then you read Malik and not Maalik. You can also get Warsh Mus'hafs (copies of the Qur'an) which have it written as Malik. Maalik is correct for Hafs an Aasim, and Malik is correct for Warsh. I am talking about its occurrence in Surah al Faatihah only here.
Both recitations have a basis, as explained in the link in my previous post, therefore we must not think the other person to be reciting to be wrong because we haven't heard it recited like that before. This hadeeth is worth noting:
Narrated `Umar bin Khattab:
I heard Hisham bin Hakim bin Hizam reciting Surat-al-Furqan during the lifetime of Allah's Messenger :saws:, and I listened to his recitation and noticed that he recited it in several ways which Allah's Messenger :saws: had not taught me. So I was on the point of attacking him in the prayer, but I waited till he finished his prayer, and then I seized him by the collar and said, "Who taught you this Surah which I have heard you reciting?" He replied, "Allah's Messenger :saws: taught it to me." I said, "You are telling a lie; By Allah! Allah's Messenger :saws: taught me (in a different way) this very Surah which I have heard you reciting." So I took him, leading him to Allah's Messenger :saws: and said, "O Allah's Messenger :saws:! I heard this person reciting Surat-al-Furqan in a way that you did not teach me, and you have taught me Surat-al-Furqan." The Prophet :saws: said, "O Hisham, recite!" So he recited in the same way as I heard him recite it before. On that Allah's Messenger :saws: said, "It was revealed to be recited in this way." Then Allah's Messenger :saws: said, "Recite, O 'Umar!" So I recited it as he had taught me. Allah's Messenger :saws: then said, "It was revealed to be recited in this way." Allah" Apostle :saws: added, "The Qur'an has been revealed to be recited in several different ways, so recite of it that which is easier for you."
Sahih al Bukhari 5041
http://www.sunnah.com/bukhari/66/65