What is a deadlock and what is a live lock ?

Deadlock is a situation when two processes, each having a lock on one piece of data, attempt to acquire a lock on the other's piece. Each process would wait indefinitely for the other to release the lock, unless one of the user processes is terminated. SQL Server detects deadlocks and terminates one user's process.
A livelock is one, where a request for an exclusive lock is repeatedly denied because a series of overlapping shared locks keeps interfering. SQL Server detects the situation after four denials and refuses further shared locks. A livelock also occurs when read transactions monopolize a table or page, forcing a write transaction to wait indefinitely.

Error Number: 1205

Steps to resolve dead locks:
Although deadlocks cannot be avoided completely, the number of deadlocks can be minimized. Minimizing deadlocks can increase transaction throughput and reduce system overhead because fewer transactions are:
• Rolled back, undoing all the work performed by the transaction.
• Resubmitted by applications because they were rolled back when deadlocked.
To help minimize deadlocks:
• Access objects in the same order.
• Avoid user interaction in transactions.
• Keep transactions short and in one batch.
• Use a low isolation level.
• Use bound connections