Graffiti?

In today’s world, graffiti have made known in (has been made known to have is past tense and doesn't work for this situation. The rest of the sentence has to agree with the present tense) society and are (is Graffiti is singular) no longer something weird drawn on a wall. It is (not wrong but you should use it's, especially in normal speach) true that many of the arts don’t provoke as much agitation as this does. However, as graffiti is a new type of art, it’s necessary to (again not wrong, but should works better in this situation) be considered.
Some people argue that there is no art in graffiti and it is often said that the artists are just untalented hooligans damaging the urban furniture (furniture are things like couches and chairs. Envitheronment is a better word). This is what citizens fear; streets neglected by the local government converted in a blank canvas for graffiti artists.
However, if artists have the chance of showing their paintings in a gallery, this point of view could be changed little by little. In contrast to them, some other people believe that graffiti artists are better than politicians of (at of is possessive) telling the truth just the way it is.
Economical and politician situations are on exhibit in graffiti without the regard of governments (not wrong, but doesn't make much sense) as the famous graffiti drawn in (on. In would be "inside" on is "the serrface") Palestine’s wall showing a girl being raised by a bunch of balloons. Usually, graffiti artists are never seen and they are known only by their pseudonyms which facilitate those (not needed) complaints.
In conclusion, the arts should be respected in whichever (not wrong, but whatever sounds better in this case) form. Certainly graffiti may not convince everybody but an art that helps to promote implications must be esteemed.

Thanks for the corrections!

Good job. A few minor errors but nothing important. Your vocabulary and grammer is quite good.