I want to show a difference between characters while conversation in a chapter by using italics.so, that readers can understand the conversation without any confusion. is it a proper way? can I do it?
I use dialogue tags... can I use italics too?..for differentiating the conversation between two characters?
But the purpose of dialogue tags is to differentiate the two characters. Why do you want to also use italics? It's definitely not a normal use of italics.
You can do whatever you like, but be aware this is not the convention in English. Better to use dialogue tags, as @ChickenFreak suggested. Even better to use 'beats', because beats give you additional information as well as just letting on who is speaking. Beats are something like what Brian does here: "Get out," Jane said. (dialogue tag) Brian marched to the door and seized the doorknob. "Don't panic." He yanked the door open. "I'm leaving." (beats) You can use italics any way you like, but if they stretch to more than a sentence or so, they can be difficult to read. If you use them for attributing dialogue, you will be unable to use them for anything else without really confusing the reader. (For example, if you wanted to use them for a foreign word or phrase. Or simply for occasional emphasis.) Also, consider what this would be like if the story was to be read out loud, with nothing but italics to differentiate between speakers. And what would you do if you have more than two speakers in a scene? There would be no way for the listener to figure out who was saying what. Audio books are now very popular, so I think this sort of thing needs to be taken into consideration when you write. I'm not a hater of italics, but I'd say be cautious about using them for this purpose. You might be creating more problems than you will solve.
Italics are overused, and most uses are not in accordance with style guides such as the Chicago Manual of Style. If you don't care about that, know that italics aren't as easy to read as plain text. I understand not wanting to use dialogue tags any more than necessary. But many dialogue tags aren't even necessary, even with more than two participants in a conversation. You can also use beats (short action sentences between dialogue fragments in place of tags). See my Table Talk blog entry for an example. Italics definitely have legitimate uses in fiction, and in writing in general. But they are ugly, especially in large blocks of text, and there is nearly always a better way.
Heya friend! Tags are essential to start a conversation between characters. Italics usually are used in interior dialogue. Why not creating a voice to your characters? How? Very simply. Let's imagine one of your characters is a businessman: 'Ladies and gentlemen, today we will discuss the economics of our company. Ms Malcom, would you like to show us your reports today?' Instant, for example, another character is a student, a young man that is in high school: 'Dude! Did you saw the move yesterday of X-Men? Man... that was sick! As you can see these two characters have a different voice, and the reader will understand that while reading your book. Just think about their occupation, their lifestyle or a particular aspect of their life, or even their past. I hope this helps. Keep on good work and have fun with your project!
There's a whole thread (from hell) on using italics for thoughts or not, but the only time I've seen them used in dialogue to distinguish speakers was when one of the speakers was using a non-vocal or otherwise indirect form of speech such as telepathy (which is a variant on italics for thoughts). I think I've seen them used to indicate that the voice was coming from a phone, radio, or other speaker as well, but I would definitely not use them for in face to face vocal communication.
You can do it, but why would you? Books are full of conversations between two or more people and no one uses italics to distinguish who is talking. I’ve seen it for non-verbal speech or interior monologue, but that’s about it. You can do it but I don’t see any benefit from it so why?