Four of the challengers in this years vote in Algeria have previously run for election.
In the upcoming Algerian elections, scheduled for 17 April, incumbent Bouteflika faces five candidates as he seeks his fourth term in office. Below are short profiles of Bouteflika and his challengers:
Bouteflika, 77, first came to power in 1999 and was re-elected in 2004 and again in 2009 after having amended the constitution to allow him to stand again. He is credited with helping end Algeria's civil war in the 1990s that killed 200,000.
Born in Morocco on March 2, 1937 to a family of Algerian origin, he enlisted in the army in 1956 to fight against French colonial powers and is a veteran of the war of independence.
He served in parliament and at the age of 25 was appointed minister of sports and youth, and later as foreign minister.
The last years of his rule as president have been dogged by corruption scandals implicating members of his inner circle and speculation about his health after he underwent surgery in 2005 for a stomach ulcer.
In April 2013, he was hospitalised in Paris after suffering a mini-stroke, returning home looking frail three months later. Since then he has chaired just two cabinet meetings and appeared rarely in public.
Benflis, 69, is considered Bouteflika's key challenger. A former prime minister, he decided to stand in the election after a 10-year absence from politics after he lost the 2004 poll.
Born in eastern Algeria on September 8, 1944, Benflis studied law, served as a justice minister and co-founded Algeria's League of Human Rights in the 1980s.
In 1999, he ran Bouteflika's campaign a trusted aide who later headed the ruling National Liberation Front. But in 2004 he ran against the president and won only 6.4 percent of the vote, while Bouteflika was re-elected with 85 percent.
The only woman in the race is 59, a member of parliament and a prominent leftist politician who ran in two previous presidential contests.
Born April 7, 1954 in eastern Algeria, Hanoune heads the leftist Workers Party and co-founded an association for equal rights between the sexes in 1989.
She was arrested twice in the 1980s when she worked for a clandestine socialist workers' group.
Touati, 60, set up the Algerian National Front in 1999 and is a former soldier who was trained in Syria and in Libya.
He has stood as a candidate in two previous presidential elections.
Born October 3, 1953 in central Algeria, he worked for the customs authority and has headed a committee set up to defend the interests of children of those killed in the war of independence.
Ali Fawzi Rebaine
An optician by trade, 59-year-old Rebaine co-founded Algeria's first human rights group in 1985 and three years later helped set up a national anti-torture panel.
In 1985, he was arrested and sentenced to 13 years in prison on charges of undermining state security and membership of an illegal association. He was freed under a presidential pardon two years later.
He was born January 24, 1955 in Algiers and heads the Ahd 54 party.
This is the third time he stands in a presidential election.
A first-time challenger for the presidency, Belaid is the youngest of the six candidates at 50.
He has headed the opposition El-Moustakbel Front since 2012, after quitting the ruling National Liberation Front of which he was a member since he was 23.
He has a PhD in medicine and a degree in law.
Belaid was born June 16, 1963 in Batna, the hometown of key challenger Benflis.