Hey guys can you tell me about abraham lincoln's nickname "honest ab"?

There are various theories on the origin of the nickname "Honest Abe." When Abraham Lincoln was working as a clerk in a store in New Salem, he once took 6 1/4 cents too much from a customer. That night when the store closed, he walked three miles to return the woman's money. Another time a customer who asked for 1/2 pound of tea was mistakenly given only 1/4 pound because Lincoln had absent-mindedly left a 1/4 weight on the scales. Very early in the morning, when he discovered the mistake, he walked a long way to give the customer the right amount of tea. Another theory is that it had to do with Lincoln's honesty in judging horse races in the New Salem area. A final possibility was his habit from early on in his legal career to charge little or no legal fees when he knew his client was poor. Other Lincoln nicknames included "The Rail Splitter," "The Great Emancipator," and "Father Abraham." "The Great Emancipator" refers to Lincoln's issuance of the Emancipation Proclamation and his strong support of the Thirteenth Amendment which ended slavery in the United States. "Father Abraham" refers to Lincoln's leadership during the Civil War and his goal of ending slavery. 

The Illinois Republican State Convention was held in Decatur in 1860. During that convention, John Hanks, Abraham Lincoln's cousin, carried two rails down the aisle. He also carried a banner which said, "ABRAHAM LINCOLN The Rail Candidate for President in 1860 Two rails from a lot of 3,000 made in 1830 by John Hanks and Abe Lincoln, whose father was the first pioneer in Macon County." Hanks became famous for his role in creating the "Rail Splitter" candidate for President! Thus, this nickname recalled the days when, as a young man, Lincoln had split logs to make fence rails.

Very useful. it is to learn because history repeats itself so learning about it those mistakes not happen again.