A "scared" but resolute Lindsay Lohan began a 90-day jail sentence on Tuesday, trading nightclubs and Twitter messages for a small, isolated cell and an orange jumpsuit.

Lohan, 24, was booked into an all-female jail in south Los Angeles for violating her probation on two 2007 drunk-driving and cocaine possession charges.

The actress is likely to serve just 14 days behind bars, said Steve Whitmore, spokesman for the Los Angeles County Sheriff's Department, which runs the jail system.

Whitmore told reporters that nonviolent female inmates generally serve about 25 percent of their sentence. Good behavior and jail overcrowding programs also reduce the time in L.A. lock-ups, he said.

Beverly Hills Judge Marsha Revel on Tuesday ordered that Lohan must not be released to house arrest or electronic monitoring.

The "Mean Girls" actress, whose promising career has foundered during two years of strenuous partying, looked tired and tense during a brief, silent appearance at a packed Beverly Hills courtroom on Tuesday morning, where she was handcuffed and taken into custody.

Lohan's lawyer, Shawn Chapman Holley, told reporters Lohan is "scared as anyone would be...and she's resolute. She does her time just like anyone else."

Local TV news helicopters showed live video of Lohan's journey, an unmarked car with tinted windows, to the 2,200-bed Century Regional Detention Facility.

Whitmore said that Lohan "has been extremely cooperative and everything is going smoothly."

She will wear a standard orange jumpsuit, hand in any jewelry, and cellphones and computers are banned.

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Lohan, who has voluntarily spent the past week in a sober living facility in Los Angeles, will serve her jail time alone in a 12 ft by 8 ft (nine square-meter) cell for her own safety.

"People that have this kind of notoriety...they are kept away from the general population," Whitmore said. "We call that a keep-away."

Lohan seemed philosophical about her plight on Monday. "(T)he only 'bookings' that i'm familiar with are Disney Films, never thought that i'd be 'booking' into Jail... eeeks," she wrote on Twitter on Monday evening.

Revel sentenced Lohan to jail after ruling that she had missed multiple alcohol education classes imposed in 2007.

Lohan must also attend a 90-day residential rehabilitation program on her release from jail, delaying shooting on her next, independent movie in which she will play the late porn star Linda Lovelace.

Lohan's estranged father, Michael Lohan, who claims Lindsay is addicted to prescription medications, said he spent the morning praying for his daughter. "He is devastated she is going to jail," his representative told reporters.

Lohan found fame at age 11 in a remake of "The Parent Trap," and her subsequent work in "Freaky Friday" and "Mean Girls" established her as one of Hollywood's most promising young actresses.

But her career has declined since 2007 when she admitted she was addicted to drugs and alcohol, made three trips to rehab and spent 84 minutes in jail. On release, she returned to a hectic night-clubbing schedule.

Lohan's next movie "Machete", a thriller in which she plays a socialite with a penchant for guns, is due for release on September 3 and will be distributed by 20th Century Fox.