No.
Yes, there is online multiplayer on Call of Duty 4: Modern Warfare.
No, you can play splitscreen spec ops and offline multiplayer though
I would say that Call of Duty: Modern Warfare 2 is better, because of the weapon selection, perk selection, graphics, gameplay - both multiplayer and singleplayer storyline, the killstreak reward selection, the offline multiplayer class customization feature, and the online multiplayer gameplay. Everything about Modern Warfare 2 is better. Except the price.
Call of Duty World at War, Modern Warfare, Modern Warfare 2, Black Ops, and Modern Warfare 3 all have online multiplayer.
Multiplayer is free.
No. It's online multiplayer
Yes - multiplayer is free
yes u do, and u have to get a 25 killstreak
yes there is in my opinion it is better than mw2 mulitplayer
Sadly, you cannot get gamer score points in CoD: 4 Modern Warfare Multiplayer.
Online and offline.
10th prestige Level 70 as Online and Offline have the same level and prestige Caps.