In Call of duty 4 (Or Cod4:mw, Cod4) Promod there are different variations of skill levels. This means that some players are more advanced than others. These skill levels include:
New players to competitive gaming, but not new to gaming. You should be able to hold your own against any other low skill team. You should be learning what tournaments are around such as Vita Nova, Multiplay's insomnia and Dreamhack.
You will be experienced at playing wars, but you may lack the high skill ability due to your age, or purely from your lack of coordination/game sense.
Only here to fill the gap between people who aren't good enough to claim themselves high skill, but are to up themselves to admit they're med skill. The only difference between a med and a med+ player will be their level of keeness. Meaning it's more likely they'll know better grenades etc.
The only difference between a med and a high player will be their level of keeness. Meaning it's more likely they'll know better grenades etc. You will have better game sense and should be able to hold your ground against teams who claims to be High skilled. Possibly LAN experienced and has had many games and matches within leages and ladders.
You will be highly skilled at the game. Have participated in multiple online events and ideally some offline too where you have achieved good results. Not necessarily high finishes, but some good wins.
You will be able to hold your own against a pre.invite team and perhaps even beat them in PCW's. To join academy skill events, you must apply to join it. Here
You should only claim yourself to be Pre.invite skill if you've actually been in a Pre.invite team that has passed the pre.invite acceptance process. Also you should actually have been playing consistently since that time. As with the academy skill you also need to apply. Here
These skill levels have been taken from Tek-9.org.