Rihanna, Reba & More Celebs Tweet Memorial Day Messages: 'Cheers To The Troops!'

LOS ANGELES, Calif. -- From primetime darlings and reality stars to athletes and pop princesses, celebrities across the USA are taking a moment to honor America's finest on Memorial Day, remembering those fighting, those who've come home and those who've given the ultimate sacrifice for freedom.

Here's what the stars are Tweeting:

Kaley Cuoco: Let this beautiful day remind us of our fallen armed forces and those who are still risking their lives for us every day. Never Forget.

Rihanna: Happy Memorial Day!!! #CHEERS to the troops!!! And to their wonderful families! You are the heart of this Nation and We love you so much!

Ralph Macchio: Take a moment to honor our servicemen and women today! #MemorialDay

Blair Underwood: Thank you to all the men and women who serve and have served in our military. I am forever grateful to my own father's service to his country & family. Col. (Ret.) Frank Underwood served 27 years in the US Army.

Chris Jericho: To all of the brave warriors who paid the ultimate sacrifice while protecting this country, I remember and salute you eternally...

Gabrielle Union: Remembering our fallen soldiers, all members of the armed forces & their families on ths day & cont 2 pray 4 the wounded.

Reba McEntire: I hope you all have a very safe Memorial Day. Much appreciation goes out to our service men and women

Joey McIntyre: Thank you to all those brave men and women who gave their lives for our freedom. We remember you always and especially today. Thank you.

Teresa Giudice: To all the military men and women and their families who sacrifice so much for all of us... THANK YOU! We love you! Happy Memorial Day! xx

Jeri Ryan: This Memorial Day, please remember our fallen heroes. And thank a veteran/soldier.

Chris Daughtry: Happy Memorial day everyone! Very thankful for the people who have served and continue to serve our country! God bless you!

Travis Barker: 2day give thanks & salute all of those who have served & died so that we may live in freedom , in hope 4 peace. Much love #HappyMemorialDay

Jordin Sparks: Happy Memorial Day! Really missing @brianohler!

Dina Manzo: Happy Memorial Day~BIG Thank you to all who have served & remembering those who gave their lives to protect our freedom. God Bless...

Mark Sanchez: Gr8 day to celebrate our freedom & remember that this is the home of free b/c of the brave. God bless our troops

Jon Favreau: Remembering those who gave their lives protecting others. #memorialday

Kellie Pickler: Saluting our service men, women, and veterans!! #HappyMemorialDay

Rebecca Mader: Happy Memorial Day America. I'm thankful for those who have served this great country!

David Archuleta: It's important to remember!! All that people have done for us to influence what we've become today. Happy Memorial Day!

Fran Drescher: Bless r service men & women who made the ultimate sacrifice 4America. R u seeing the ads 4Happily Divorced everywhere? So exciting! Ate2much

Gilles Marini: To all our men and women who fight for our country! Thank You and to the Families who's soldiers have fallen they will never be forgotten.

Stacy London: Happy Memorial Day. A huge thanks to all who have defended and continue to defend this country. My thoughts are with you and your families!

Star Jones: Thanks to the men & women who "stand on the wall" for our freedom and way of life. I'm truly grateful for your service. #MemorialDay

Erin Andrews: Thank you to all the service men, women, and families on this Memorial Day. We are forever grateful.

Macy Gray: Good moanin. Happy Memorial Day. Don't forget.

Matt Lanter: Happy memorial day! Let's not forget why we celebrate this day.