Credits

Credits are the standard galactic currency, and are used to purchase weapons, armor, and upgrades.

History
The standard credit ass established by the Citadel's Unified Banking Act, a piece of legislation enacted by the Citadel Council establishing the credit as the standard galactic trade currency. The legislation was drafted by the volus, due to their expertise in financial and commercial matters. The Act also laid out regulatory guidelines for determining the value and exchange rate of the credit in relation to the currencies of the individual Citadel member races.

The credit has a managed floating exchange rate, calculated in real time by the central bank to maintain the average value of all participating currencies. Some regional currencies are worth more than a credit, and some less. When the Systems Alliance joined the Citadel, its various national treasuries were linked into the credit network. A human with a bank account of Mexican pesos, Japanese yen, or Indian rupees can purchase any item priced in credits at fair market value. All economies that participate in the credit network are required to price items in both local currency and credits.

Hard currency can be stolen or counterfeited, so electronic fund transfers are the norm. More importantly, physical transactions cannot be easily tracked, making them ideal for tax evasion or the purchase of illegal goods.

Gameplay
In Mass Effect, Commander Shepard is limited to a maximum of 9,999,999 credits. After this cap is reached, no monetary rewards for completed quests will be given. Any items sold to merchants will also effectively be given away for free. Upon reaching this limit, it is advisable to convert any unwanted items to omni-gel rather than to sell them; alternatively, the player may keep them around to sell later after buying something. Mass Effect 2 has the same credits cap as the first game, although reaching this limit requires cheats / exploitation.

Mass Effect 2
Unlike Mass Effect, credits are fairly sparse, especially without DLC. See the Upgrade Guide and Armor Customization sections for information on the costs. In short though it is recommended to sparingly mine only what you need to. With all DLC installed and completed, coupled with level 60 import bonuses and the bonuses from previously completing a Mass Effect 2 playthrough, it is possible to purchase everything in the game including the cabin accessories such as model ships and fish.