MT4 / MQL4 entry to the master of EA course lesson two - commonly used functions

AccountBalance(); // Returns the current account balance.
AccountEquity(); // Returns the equity of the current account.
AccountFreeMargin(); // Returns the available margin for the current account.
AccountMargin(); // Returns the current account used margin.

Hour(); //Returns the current server time
Minute(); //Returns the server time in minutes
Seconds(); //Returns the server time in seconds

iOpen(); //returns the open price of the bar
iClose(); //returns the closing price of the bar
iLow(); //returns the lowest price of the bar
iHigh(); //returns the highest price of the bar
iTime(); //returns the time of the bar
iVolume(); //returns the volume of the bar

IsConnected(); //Whether to connect to the server
IsDemo(); //Whether it is a demo account
IsDllsAllowed(); //Whether it is allowed to load DLL files
IsExpertEnabled(); //Whether it is allowedAutomatic trading
IsStopped(); //Whether the EA interrupts execution
IsTradeAllowed(); //Whether trading is allowed
IsTradeContextBusy(); //Whether the transaction is busy

OrderClose(); //Order closing function
OrderClosePrice(); //Return order closing price
OrderCloseTime(); //Return order closing time
OrderComment(); //Return order comment
OrderDelete(); //Cancel pending order
OrderLots(); //Return order lot number
OrderMagicNumber(); //Return order ID number
OrderModify(); //Order modificationFunction
OrderOpenPrice(); //Return order opening price
OrderOpenTime(); //Return order opening time
OrderProfit(); //Return order profit and loss
OrderSelect(); //Order identification
OrderSend(); //New order
OrdersHistoryTotal(); //Return historical order statistics
OrderStopLoss(); //Return order stop price
OrdersTotal(); //Returns the total number of all current orders and pending orders
OrderSymbol(); //Returns the order type
OrderTakeProfit(); //Returns the order take profit price
OrderTicket(); //Returns the order number
OrderType(); //return order type

Print(); //Print log
printf(); //Print log with format

Sleep(); //Sleep function
StringAdd(); //Strings are connected, return a new string
StringCompare(); //String comparison, equal return 0
StringGetChar(); //String read character
StringSetChar(); //Add character to string
StringToCharArray(); //String change character array
CharArrayToString();//Character number changeString
StringToDouble(); //String becomes Double
DoubleToString(); //Double becomes String
StringToInteger(); //String becomes Integer
StringToTime(); //String table time type
TimeToString(); //Time class becomes string

Symbol(); //Return the current chart symbol

TimeCurrent(); //Returns the current server time
TimeDayOfWeek();//Returns the current day of the week
TimeGMT(); //Returns the GTM time
TimeGMTOffset(); //Returns the time difference
TimeLocal(); //Returns the time on the computer
TimeHour(); //Returns the hour in the time
TimeMinute(); //Returns the minute in the time
TimeSeconds(); //returns the time in
TimeDay(); //returns the current time and date
TimeMonth(); //returns the month in the time
TimeYear(); //returns the year in the time