What are presidential executive orders?

President Barack Obama unveiled sweeping proposalsWednesday to toughenU.S. gun lawsincluding an assault weapon ban and limits on magazine capacity.

Some of these proposals,such asthe assault weapon ban,will require Congress's approval, which couldprove difficult.

But othersmay be accomplished directly by an order from the president's pen.

On Wednesday, Obamasigned 23 such executive actions, which require no congressional approval,including:

• Ordering federal agencies to make relevant data available to the federal system of background checks.
• Launching a national campaign on safe and responsible gun ownership.
• Requiring federal law enforcement to trace guns recovered in criminal investigations.
• Giving schools flexibility to use federal grant money to improve school safety.

Here are some answers to questions about executive orders.

What are executive orders?

Executive orders are directives issued by the president that carry the weight of a federal law. A somewhat nebulous concept, these orders have no specific basis in the U.S. Constitution althoughthe power is typically understood to arise out of Article II, which states that "the executive power shall be vested in a President of the United States."

A U.S. government website say the orders are used to direct and manage the federal government.

They have typically been used to alter existing laws instead of creating new ones, and Congress can override an executive order by passing legislation that opposes it.

The Supreme Court can also overturn them, as it did in 1952 when President Harry Truman attempted to seize control of U.S. steel mills using an executive action.

In Youngstown Sheet & Tube Co. v Sawyer, the country's top court ruled that Truman had exceeded his authority andestablished that such orders must be based on a specific act of Congress or the Constitution itself.

Critics havedecried the use of these directives as an abuse of power.

What impact do they have?

That really depends on the particulars of each executive order. A congressional research report from 1999 noted that "there is no hard and fast rule concerning these presidential instruments."

Some, for instance, are used to create special committees, nominate candidates to federal agencies or order research into a particular topic.

Others have lead to widespread changes to the country, including a directive issued by President Franklin D. Roosevelt to relocate and imprison citizens of Japanese ancestry during the Second World War.

How often are they used?

Executive orders can be traced back to the country's first president, George Washington, although their use was limited often just a handfulover the course of one or two four-year terms.

However, inthe early 20th century, presidentsbegan to use the power more frequently.

Over the last 100 years,presidents have usually issued a number of executive orders annually, ranging from a low of about five to as many as several hundred in a year.

Both George W. Bush and Ronald Reagan, for example, issued just five of themin 1989 and 2009, respectively, but significantly more in other years.

Roosevelt, on the other hand,tallied almost 600 executive orders in 1933.

What impact will Obamas 23 executive orders have on gun laws?

A number of commentators have said that the executive orders signed by Obama represent merely one step in any attempt to overhaul of U.S. gun lawsan ambitious goal for the recently re-elected president.

Obama seemingly acknowledged this reality by saying the most sweeping, effective action must be taken by lawmakers.

"To make a real and lasting difference, Congress must act," Obama said at the Whitehouse on Wednesday. "And Congress must act soon."