What sort of mods are you looking at getting, on ecc toy can use mods such as the macro mod, optifine, cjb etc etc
Depends on the mods you are looking to use. As a very general rule though, you can use mods that do not give you an unfair advantage. The most common mods are what Sneaky mentioned, and I believe Rei's Minimap is fairly popular. If you are uncertain if you can use a mod or not, you can always ask. Some examples of mods and unfair advantages that are not allowed are x-ray, autoclickers, and hacked clients.
also you cannot use mods that ONLY work on singleplayer or servers that have it enabled such as tekkit, or any mod that adds a block or item to the game But mods that are client-side like reis minimap, macro, and cjb lite will work. But some client-side mods are illegal, like zan's minimap, nodus, player radars, xray mods, xray texture packs, really anything that gives an unfair advantage is illegal. Unfair advantage is not counted as things like light mods, it's counted as things that will make you money easily like xray and mob tracker to track things like spawners and ores and stuff.
