Brahma Had Five Head Shiva Cut off One

As I've heard before, there was a story which said that lord Brahma had five heads but the fifth one was chopped off by lord Shiva.

So why did lord Shiva chopped off the fifth head of lord Brahma?

Also, did he really had five heads or he has four as it's shown here?

One such story says that Brahma made a lady named Shatarupa to help him with his occupation of creation. As indicated by the myth, Shatarupa was beautiful to the point that Brahma turned out to be totally beguiled by her and gazed at her wherever she went. Shatarupa was humiliated by this consideration and attempted to get away from his look, yet toward each path that she moved, Brahma grew another head until the point that he had created four. The baffled Shatarupa ended up plainly edgy and started to hop to attempt to get away from his look. This provoked Brahma to grow yet another head on top of the others with a specific end goal to keep her in locate. 

It is said that Shiva scolded Brahma for his "unholy" conduct towards Shatarupa and hacked off his fifth head as discipline. Brahma had given into the longings of the fragile living creature and deserted the work of the spirit and for this current Shiva's revile was that individuals ought not venerate Brahma. 

The story additionally goes ahead to state that Brahma has been consistently presenting the four Vedas as far back as a type of atonement, one from each of his four heads.

The same story in other links too. 

Brahma Had Five Head Shiva Cut off One

Also Wikipedia Link

From Siva Purana, Jnanasamhita 49:65-80: 

Brahma sought Sarasvati and went to her, requesting that her stay with him. She, being his little girl, was angry at this and stated, 'Your mouth talks forebodingly thus you will dependably talk oppositely.' From that day, Brahma's fifth head dependably talked evilly and coarsely. Consequently one day when Siva was meandering about with Parvati and came to see Brahma, Brahma's four heads commended Siva however the fifth made an abhorrent sound. Siva, disappointed with the fifth head, cut it off. The skull stayed adhered quick to Siva's hand, and however he was equipped for consuming it, Siva meandered the earth with it for all individuals, until the point that he came to Benares.

Shatarupa

At the point when Brahma made Shatarupa, he was quickly captivated and sought after her wherever she went. Shatarupā moved in different bearings to maintain a strategic distance from his look yet wherever she went, Brahmā built up another head until the point that he had four, one for every course of the compass. Urgent, Shatarupa jumped over him to remain out of his look notwithstanding for a minute. A fifth head, be that as it may, showed up over the others. In this manner, Brahmā created five heads. As of now Shiva showed up, removed the top head and confirmed that since Shatarupā was Brahma's little girl (being made by him), it wasn't right and incestous of Brahma to wind up plainly fixated on her. He coordinated that there be no appropriate love in India for the "unholy" Brahma. 

Another adaptation of the story depicts Shatarupa as a divinity with excellence in many structures. After Brahma had developed his fifth head Shatarupa had transformed into a dairy animals to dodge his desire. At the point when Brahma discovered he transformed into a bull with a specific end goal to keep on following Shatarupa, in the end discovering her. She covered up as another creature with a specific end goal to control his unnatural desire. In any case, oh dear, Brahma discovered again and incarnated as the proper male creature. Once more, she covered up as another creature. This proceeded until the point when the majority of the creatures of various sorts in this day and age were conceived and Shiva at long last ripped off one of Brahma's five heads to put a conclusion to his desire. 

Matsya Purana, exhibits the comparative story yet its self conflicting as far as marriage of Brahma with Shatarupa and specifying Manu as their child.

Another interesting story which mentions about God Shiva chopping of God Brahma's 5th head is as follows..

Once there was a conflict between God Brahma and God Vishnu as to who was the most powerful among the Trimurti’s, while the argument was happening, a long pillar of fire appeared in between God Vishnu and God Brahma. It was decided that among them that whoever finds the end of the pillar was the most powerful. God Vishnu took the form of a boar and dug underground. God Brahma took the form of a Swan and went towards the skies, both could not find the end of the pillar and returned, God Vishnu accepted that the pillar was endless, but God Brahma lied about the pillar’s limit claiming that he was the true God.

Immediately the pillar broke open and God Shiva in rage appeared in front of both the God’s and cut God Brahma’s fifth head, when he was about the kill God Brahma, Vishnu intervened and requested God Shiva to pardon God Brahma, but told that God Brahma would never be worshiped again in the world.