One should note that correspondence and contact between the sexes is one of the doors that lead to fitnah ,temptation,. Shareeah is filled with evidence which indicates that it is essential to beware of falling into the traps of the shaytaan in this matter. When the Prophet ,pbuh, saw a young man merely looking at a young woman, he turned his head so as to make him look away, then he said: I saw a young man and a young woman, and I did not trust the shaytaan not to tempt them. Narrated by al-Tirmidhi (885) and classed as hasan by al-Albaani in Saheeh al-Tirmidhi

Both are good in their own place.